Friendly Competition at Cadwell Park

[AllanGP]

For All who like a bit of friendly competition and knowledge sharing!

This thread is for Cadwell Park.

Please feel free to post times in the Hotlap section and post your comments, Set Ups, MoTeC data here.

I've been doing a few of these with some regular Hotlappers (Animal Ed, FreddyFartBox, EddieH, to name just some) and we want to encourage people to try the selected circuits and share data so we can all go a little bit faster :-D

Knockhill is the other active thread but you will see threads for Snetterton, Croft and Mid Ohio - feel free to do laps and post on those threads too.

Allan

[Freddyfartbox]

I'm on a Porsche RSR bender ATM, I hadn't driven that much before but I've been cranking out some times in it tonight.

[animal ed]

Here is setup for elise (for my fastest lap it was slightly reworked but I didn`t save - lowering front little bit, harder springs f/r and increasing fast bump and rebound on front) and MoTec. I use red coca cola RSR (can remember teams name) with pirelli tyres ...

18540

...and :thumbup: for choice

[AllanGP]

Animal,

Looks like battle joined for the Elise time!! I'll also try the RSR here. My time in the Hotlap section was before I started to understand changing the car set up.

This was the second track I got serious about in GTR2 and probably my favourite so far.

I didn't mean to divert attention from Knockhill. I think having two tracks on the go at one time is okay and provides a bit of variety?

Allan

[animal ed]

.....
I didn't mean to divert attention from Knockhill. I think having two tracks on the go at one time is okay and provides a bit of variety?

Allan

Couldn`t agree more!

...and for Cadwell - honestly, I didn`t like it at all at the first sight, maybe because I tryed it with GT1 class car. So bumpy, up and down... but with lower classes... pure beauty and chalenge trying to keep speed knowing that you don`t have enough engine power to limit the damage if mess up in braking or cornering but in the same time discovering more that one racing line... realy excelent track.

[AllanGP]

Well Animal,

I've gone a little bit quicker in the Elise :-D over to you! I am not sure I have much more to come at this great track with that car.

I've started to try and get a good time with the RSR but still 2 secs off your pace and that was only possible by the excellent RSR set up posted by FreddyFartBox (in the Knockhill thread). I would not have believed you could make the RSR feel that good. I'm sure I can get 1 second off but two might be quite difficult.

Cadwell is great isn't it, the sort of circuit once you know it that can easily give up 4 or 5 seconds from when you first start on it or more.

As you say suits the NGT cars more than the GT1's.

[Freddyfartbox]

Thanks for setup compliment.:-D I've been using the Knockhill set as a base for other tracks, just adjusting gears where necessary. It feels quite comfortable on every track I've tried. I have to admit though the damper settings were kind of a random adjustment, still don't fully understand dampers, seems to work ok though.

I'll spend some more time at Cadwell today, I only did 12-15 laps to get my time yesterday, now Animal has beaten my time I'll have to have another crack.

[Freddyfartbox]

Well I've gone faster today, knocked about 8 tenths off last nights time. There's still more in it if I can get the car to settle down a bit more, probably some proper damper adjustments would help but I'm not sure where to go there. Better start reading up on damper adjustment then.;-)

I have a question about tyre temps, if anyone can help. Should the temp spread have the middle of the tyre between the inside and outside temps, or should the middle temp be lower than both the inside/outside?

[AllanGP]

Freddy,

Well they should rise from the outer edge to the inner edge, with, ideally (for racing not necessarily hotlapping) a maximum of 10 degrees C between the lowest (outside edge) and highest (inside edge).

If the middle is lower than the outer two it indicates too low a pressure and if the middle is higher than the outer two it indicates too much pressure.

For Hotlapping you can extend the temperature gap as you are not expecting the tyres to last :crying:

I try not to go too extreme because when I get to doing some racing I want to just turn back my settings one click and hopefully they will be good to race.

Allan

[Freddyfartbox]

Thanks for clarification, that's what I thought. The left rear is getting over pressure here (about 215kpa), but reducing starting pressures drops the middle temp too low. I only do probably 6 laps or so a run anyway.

[Freddyfartbox]

Well I gave up on the Elise, just can't get my head around driving that car. Although I haven't tried your set yet Allan, might give that a go later. I've just been hammering the RSR, love that car.

[AllanGP]

Well Freddy,

In the same way you can't get your head around my Elise time, I can't get my head around your RSR time. I can see a whole lot more laps in front of me.........

Anyway posted a Lambo time which I'm sure I can beat by 0.5 sec as the end was poor but it was late last night so stopped there.

Well I'm adding to this post as no one has posted after it. I got that 0.5 sec tonight :-D although now I am sure there is more to come.

However now I'm going to have a go at Knockhill.

[animal ed]

Allan

Finaly find time (and speed :-P ) to beat your elise time. Main setup change is actually on packers bacause a lot of bottoming in few places... with that small change I did 1:23:289 but forgot to save hotlap and in another try I was even faster.
There is 18723

[AllanGP]

Great Lap Animal but I also have had time to practice!! :-P

You can see I didn't hit every apex so maybe a few tenths to come yet.

Set Up attached.

[animal ed]

Sweeeeet! :thumbup:
4/10 to catch but I`m not able for good respond today. Just too tired, actually I think that I`ll need more than one day to beat (if!!!) your time. Yet - I will not give up! :-P

[AllanGP]

Cheers Animal,

I am sure there is a bit more to come. I have a confession,

If you follow this link:

http://www.mgnwracing.co.uk/images/history/1997/sept28r023.jpg

You'll maybe recognise the guy who is in 5th place (but 1st in Class A), setting a lap record that stood for 6 years, 3 years after I stopped racing.

It was fun while it lasted.

The Elise is the closest handling car I've found to my old MGB, however faster!!

Allan

[animal ed]

That 5th guy`s name sounds familiar! :-D
But I don`t think that this is your advantage as long as track isn`t 100% match to real world one. In fact this could be disadvantage because of mismatches comparing to real one therefore require different approach. I`we watched onboard`s from youtube and there is differences
My only real world race expirience is on two wheels and because of that I have big problem on tracks that I`m familliar with and that`s why I`m not tryin` really to hit apex, rather go around them. This problem is much less exposed in tracks wich I need to learn. But I have "luck" that only two tracks are here which I know and I hate them...:angry:
...and I found more than 4/10 but elise was realy loose! And that`s one thing that I really don`t understand - why I`m faster with overcoked tyres? On every track, no matter which car...

[AllanGP]

Animal,

Not looked at your lap but well done.

I thought after my post some people might have thought it was a little arrogant of me to put such a post up but that was not why I did it, more to explain why I could go reasonably quick at this circuit.

Anyway, I think the track is quite faithful to the real thing but I know I can go a bit quicker so your time gives me an incentive to try a little harder, well done.

I count myself as a reasonably quick driver not a really quick driver.

Also I do think it strange that the Elise seems to drive okay with all four wheels red but that is what it does.

[Freddyfartbox]

I only managed one lap in the Elise before the tyres went red, can't say I'm a fan of that car. And like you Animal it seems most of my fastest laps have been when the tyres are over heated and over inflated, and the arse end is sliding all over the place. Makes it more fun though.

[animal ed]

Allan

I don`t see nothing arrogant in your post. It`s good to have peapole here who actually raced in real life to tell us how close is this game to real racing. Ok, we still don`t have that G-force expirience and some other things but we have full insurance on cars :-D - no need to think how much will cost if I damage the car or possible injuries (pretty occasional in my ex discipline :crying:)... after all this is the game. Damn good game! If my post was "trigger" - appologies. I was also try to explain why I don`t think that you don`t have any huge advantage here in Cadwell seen through my eyes. You are just fast with elise no matter which track it is.

Freddy

Definitely more fun.:thumbup:

[AllanGP]

Animal,

Thanks. Your post was not the trigger I just re-read my post and thought it might come across wrongly.

Yes apart from the "seat of the pants" sensation I'd say GTR2 is pretty fantastic and a couple of my racing mates were sceptical but having tried my set up had to agree it was great - except missing the G-forces.

I'm saving up for one of these :-D not really, I suspect my wife would divorce me for sure!!

http://uk.youtube.com/watch?v=gWFop2FRSp0

[Freddyfartbox]

Anyone up for some friendly competition at Winton? It's a good track for the slower cars, the Corvette doesn't like the slow tight corners much but the RSR works great there.

[animal ed]

Anyone up for some friendly competition at Winton? It's a good track for the slower cars, the Corvette doesn't like the slow tight corners much but the RSR works great there.

Is it Winton raceway by Sunlap or other version? If other - where can be downloaded?

... forgot to say - I`m in! :-D

[Freddyfartbox]

Yeah it's the Sunalp one, available to d/l here. The GP layout BTW.

[EddieH]

Well I should be back in the drivers seat this weekend after breaking two fingers and a thumb. Never believe you can catch a falling 55Kg speaker cabinet!!! It wasn't even mine either, so it wouldn't have cost me any money. Alcohol has a lot to answer for.

[Freddyfartbox]

Lol, nice one Eddie.:-D

[AllanGP]

Eddie,

Hope you are feeling better!

Anyway I've posted a slightly faster time in the Elise, still not as good as Animals. I actually did it on the 19th but I'm sure I can go quicker, maybe 2/10ths :laugh:

Not getting as much time on GTR2 as I would like just now and I'm about to miss a week due to a visit home to Scotland.

Hopefully when I get back I'll find those 2/10ths!

Then I'm going to have to re-do my laps at Knockhill as my others have been deleted for being on the wrong version.

Then I'll try Winton!! Hope you boys are not too far ahead by the time I get there. :-D

[EddieH]

Slightly!
But I think I'm gonna move to Winton GP. It was one of the first I downloaded and haven't driven it in ages, so that's where I think I'm gonna start!

[animal ed]

Have a nice time at home in Scotland Allan! I don`t know are you familiar with Winton but, if not, I think you will like it. Main key to be fast is perfect smooth line ... lot of coasting. Freddies lap with rsr is beautyfull to watch and I don`t understand how I was able to be faster but I`m waiting for "answer" that will come certainly...

Eddie, Eddie, Eddie... nobody told you not to catch anything heavier than 1kg while drinking... unless it`s damn good looking girl worth of pain that you`ll have... :-D
Get well soon - your G25 miss you...

Freddy - :thumbup: for choice...

[AllanGP]

Animal,

Well it has taken 3 weeks (excluding a week in Scotland) and about 250 laps but I finally did it!!

I've attached my MoTeC and VCR file.

Hopefully you won't beat it too soon and I can try out Winton GP :-D

I am, as you can imagine very, very happy!!

Allan

[animal ed]

Nice to see you`re back :-)...and I`ll go back to Cadwell...again.:-P

Not today. I`we been involved too much with stop and go cars lately (read - GT1 class) and I need to get a grip with that small light thing called elise again.

[animal ed]

After more than 200 laps, over 100 laps below 1:23, at least 30 laps 1:22:5-something...faster by fraction with not that much promissing lap - finally! :clap:

Here is 19370 and setup and lap is uploaded on hotlap section. I think that I will wait little bit with Winton. GT`s doesn`t suite me on this track so I will wait NGT or G2 class cars challenge while trying to do something about Eddies times on AMS Renault track.

[AllanGP]

Well it looks like I will have to do a few more laps at Cadwell!!

I can't have you faster in both the Elise & GT's!!

Hopefully I can find 4/100ths of a second in the Elise :-D

I must admit I did not think my fast lap was going to be that quick but suddenly I found 4/10ths and so stopped.

Then I'll have to try Winton - given it a quick go but I'm still getting my rhythm there - nice track.

[carham]

This analysis has been undertaken because of the very flattering request of AllanGP, who like all racers I know, when pressed to "find something...anything" to help them go faster, will leave no stone unturned. :laugh:

The advanced state of competition in this instance has produced a well driven lap and a well developed car set-up. I ran a few laps to orient myself somewhat to the Elise; I am familiar with the track. The excellent effort put forth by AllanGP in this instance, will make it difficult to offer useful suggestions, but at my stage in life, embarassment no longer frightens me...so here goes:

Ref:

Lap time: 1:22.387 sec. Driven by AllanGP
VCR file: #82-387.zip
Track: Cadwell Park version 2.1 by Motorfx & Philrob

Driver: Excellent technique throughout, aggressive use of throttle and efficient braking and cornering, very methodical, very disiplined.

Engine:
Full use of the engine is limited by the fixed tranmission and axle gearing.

Engine oil temperature at 82 C was not at the optimium of 95 C. With water temp at 176 F (rad opening setting at 3) I suggest closing down the opening to get the small gains in performance and aero.

Powertrain Transmission: No comment.

Powertrain Differential: (-/25/40/02)

More typical settings would be to reverse the Power and Coast values, but there is no evidence to suggest that as an improvement.

However, throughout turns #3 & 4, the DIFF is fully locked. Turns 3 and 4 are at the end of the long straight. Under full power exiting turn #3, it can be seen that the car understeers itself right up to the track edge in between the two turns. Continuing, it appears that the driver reacting to this near miss, then oversteers slightly going into #4 and misses the apex putting the right side wheels momentarily on the grass, leaving the car effectively on three wheels (5300 ft point, 33 sec.). Because there appears to be no "pump" function in this DIFF, the right rear then overspins causing a major loss in grip (0.7 g's loss) and a possible reduction of torque on the outside driving wheel. It's my suspicion that the locked DIFF may have influenced the understeer in turn 3, which then contributed to the miss in turn 4.

I would experiment by reducing the DIFF power setting...maybe to zero and reducing the preload to 01 (-/00/40/01). To see if the car becomes easier to steer through 3 & 4 with full power applied. The first attachment (#7A), is a plot showing the wheelspin.

Brakes: Very good technique; balance appears good. No suggestions.

Tires: All temps look OK with proper distribution across tire. Leave camber,caster, pressures as they are.

Friction Circle: Very good. Lateral g' at +-3.0

Chassis Springs/Shocks/Rollbars: Generally appear OK; I have no suggestions. Lot's of chassis movement from 0.0 ride height to over 6.0 in. The 6.0 in. situation occurs at the track depression going into turn 2, but the wheels remain in contact with the track, which is good..

Ride Height Static: Front=2.362 in (min. avail. setting), Rear=2.935 in.

The second Attachment (#6), shows a scatter plot of the ride heights vs car speed at the four car corners. I use the individual data points to show me critical conditions (such as grounding out), or, to observe how weight transfers through various places on the track. The trend lines show the average ride heights at the corners as a function of speed.....this is very useful in getting the car in a generally level attitude at high speed for areo considerations. This attachment (#6) shows the car with about a 0.3 in. tail-up attitude at the fastest point. My suggestion is to reduce this difference to zero as best you can, especially at max speed. It will reduce the aero drag on the body and will reduce the rear wing angle a smidgen.

At nearly all the maximium "g" points, especially in turns #1 thru #4, the car hits the ground (outboard side) and on uphill transitions. See the third attachment (#3) for graphical examples in turns 1 and 2. The replay confirms several instances of the car grounding out under different conditions. I would expect that when the car hits the ground that: 1.) speed is sacrificed, and 2.) lateral g's are limited in the turns....maybe only slightly, but you are looking for all the small gains available.

My number one suggestion is: stop the car from hitting the ground. First, I would try raising the ride heights (keeping the car level) leaving all else as it is now. Second, I might try limiting the suspension travel with blockers. After that..... your ideas will be better than mine.

That's it for now.
Your comments will only help me to learn.
Good Luck,
Carham

[AllanGP]

Carham,

Fantastic, thanks.

I will try your ideas, I've never used packers, principly because I've never understood how to use them (I know Animal Ed uses them). In terms of set up I'm a novice but I'm looking forward to learning more since I've really only started using GTR2 properly since January. What I have heard were "packers" were essentially a last resort - but in this case I am looking for a last couple of tenths so maybe I'm there but just didn't realise it:-D

So lot's of good ideas to try and I will hopefully get a chance to do so tomorrow.

Thank you again.

Allan

[animal ed]

@ Allan
If I have more than two high speed bottoming I will try with stiffer or higher suspension setup (maybe both) which is generally speaking, slower because of lower grip and bouncing over bumps. For one or two bottoming per lap I use packers - bottoming in that case steal less time then without them and setup is not compromised for majority of track. On Cadwell I have two high speed bottoming = packers! It works for me.

@ carham
Really interesting analysis.:thumbup:
I found some valuable ideas (levelling car height on high speed) for me therefore I also own You gratitude.

Regards

[AllanGP]

Well Gents,

Using all the help I can (thanks carham :-D ) I've managed my fastest lap at Cadwell in the Elise - the top time for now until Animal beats it!!

The only thing I haven't done is raised the ride heights and I've only used the first click on packers - so far. So there might be more to come.

I've no doubt that the diff settings helped although I'm not sure how to describe the feeling it feels a little "looser" if I was a betting person I think it might need a click on power pre-load, so I might try that.

I lowered the rear and given I new that carham was suggesting raising the height I decided to use one click of packers first - fundamentally I don't like the idea of raising the C of G and given I could drive the car around even though it was bottoming I decided to give it a go.

It was obvious that this set up was going to yield a better time (was I imagining it but did my G25 feel more lightweight in my hands??) anyway apart from that whereas I occasionally did 1.22's before, with this set up I can do them regularly (50% of the time).

So it was just a matter of time, about 40 laps in fact.

So a massive thanks to carham - I just hope Animal doesn't go much quicker too soon.

Also I think there is more to come, we shall see.

I've attached my .vcr, .svm and two lots of MoTeC data one for the fast lap and one for a lap that was 1.22.352 my second best lap.

Finally I don't think my fastest lap was as well driven as the one already analysed by carham - of course that might be my imagination - but I think there is still more to come in my driving.

[carham]

Good job Allan,

It's difficult to judge this gain with any real confidence; however, in light of your comments and some evidence in the Motec data, it seems you've made a real gain. Racers and statisicians will never agree on a definition for "significant". :laugh:

My comments.....whether or not you want them:

1.) Leveling the car above 105 MPH, and warming the engine oil up by 8 deg C delivered about what I expected:

Speed on Pit-Straight.....2.4 MPH gain to 132.7 MPH
Long Straight................0.8 MPH gain to 133.4 MPH

See the last attachment (scatter chart).

2.) Adding 0.039 in. packers seems rather timid in light of the large amount suspension travel being used. The chassis still hits the track frequently....I'm thinking you need an "order of magnitude" larger number. Add until it stops dragging on the track, then make a judgement. I do agree with you and Ed: explore the packers first before you upset the set-up too much.

3.) DIFF SETTING:
"I've no doubt that the diff settings helped although I'm not sure how to describe the feeling it feels a little "looser" if I was a betting person I think it might need a click on power pre-load, so I might try that."

Your expressed "feeling" is interesting......you've learned to expect a car that understeers (pushes) moderately with power on. Now it feels slightly "loose" to you. All I can add, after watching super slo-motion replays (from overhead), is that the understeer I saw, especially in turn #3, has been significantly reduced......not everywhere, but in most places. My impression is that the car is not loose. Also, I see more of tendancy for the car to slightly "drift", or slide, into and through some of the turns. You may be describing the same thing by saying it's "a little looser". Your line looks good through turns #3 & 4. Work with this some more......use slo-mo replays to correlate what you feel with what you see. The car looks more "neutral" to me...but, you're the driver.

4.) Speaking of the Driver:

In both the 1:22.387 lap, and again, in the 1:22.242 lap, in turn #2 (at about 2383' or 14.04 sec.) you rode over the right curb. At this location, you are pulling 3.14 lateral g's; hitting the curb adds 1.23 verticle g's . This combination of max lateral and verticle forces pushes the left side down onto the track. See all the attachments.

The Motec data shows that forward speed is momentarily reduced by approximately 3 MPH which may be effecting your top speed down the long straight. The curb and hitting the track is subtracting speed.

Just my quick impressions, I hope you don't mind my comments,
Carham

[Freddyfartbox]

Wow that's some very in depth analysis, I wish I knew enough about setup and technique to analyze my laps like that.

[animal ed]

Allan, you should really raise that elise! In your case with that much soft suspension - packers are not enough! With even slightly "higher" setup you could gain at least 1/10. The car will still hitting ground but not that much hard - if you are not comfortable with stiffer suspension. I`m using packers just because my suspension setup is enough stiff (barely) for this choice. I was faster again by fraction :clap: only with rising car for one click - it doesn`t feel better but stopwatch says different! Carham told us - stop hitting ground! Twice!! We should listen him... (thanks grandpa :thumbup:)

[AllanGP]

Hey Animal,

Well done.

Tried two more packers all around (1.22.550) and 3 more (1.22.468). So not faster - yet - it feels quicker but to be honest I'm driving like a bit of a dick**** tonight which sometimes (often!) happens.

Will try raising the suspension tomorrow if I get time and post all data.

May turn out to be next weekend though as I've a busy few days at work.

Allan

P.S. I don't think 2/100ths will be difficult to get though :-P

[carham]

First, nice going ED!

If you guys feel I'm hijacking this thread please tell me so....no problem....OK?

Because, you (Allan & Ed) both indicated interest in more instruction on using Motec and replays to assist with set-up decisions, I've gone a little deeper for you....see below. Remember, Motec only provides data....the thinking comes from you. You're both already very savy and good at GTR2, so I think you'll follow my analysis.

Allan said the car felt "loose" (1:22.242 lap), and I said the car looked "neutral" so, we have a good opportunity to investigate a driver's impressions using the Motec and replay data. We will use the entry to turn #3 because, it can explain the "loose" feel and my "drifting" impression:

Allan followed his normal routine of: closing the throttle, and then braking down for the entry to the turn, but two things were different this time: 1) he was slightly quicker than in the past (+0.8mph), and 2) he began turning-in before releasing the brake. This created the dynamic condition of -1.041 longitudinal g's and -1.226 lateral g's. In addition, at just about the 26.836 sec. point, the 3-2 downshift occurred adding more braking effort on the rear wheels.

The above info is present in the Motec data shown in the first Attchment (#13A).

The dynamic condition began transferring chassis weight from the RR corner to the FL corner. See the second Attachment (scatter chart #13B).

Unloading the RR wheel with the brakes still applied resulted in the brake (RR wheel )to overpower the DIFF and allowing differental action (15%). Therefore, the brake slowed the unloaded RR wheel to the point that it began slipping relative to the track with a resultant loss in rear grip. See the third Attachment (#13C) which is the DIFF chart.

I believe, the loss in rear grip is the explanation for the unexpected yaw increase and steering correction (felt and made by Allan), or the "drift" I observed in the replay. See the last Attachment (#13E).

I'm not discounting Allan's impression that the DIFF set-up changes made the car "loose". I'm only saying that the data from turn #3 says there was a loss in grip not caused by the DIFF.

Thus ends the Motec/set-up lession for today.....if you don't agree, I'd like to disscuss your feelings.

Cheers,
Carham

[AllanGP]

Carham,

Have you ever considered changing your name here to "fantastic carham" you should!!

For me your not highjacking this thread, as Freddy said "Wow" I wish I knew 20% of what you do it would be great.

Keep the info coming and on reflection my description was more due to searching for the right words - I've never given racing feedback like this to anyone before - so your analysis on what I felt is exactly right.

In fact I'm sure the reason I did not go quicker last night is because I was doing more of what you describe above.

Traditionally in a low powered MGB you did everything to keep your momentum so you braked as late as possible but I think in GTR2 I need to be a bit more professional about my driving and think more modern - come off the brakes earlier than 18 years of racing taught me to do in an MGB, then turn in and get back on the power earlier.

Anyway just dashed this off to say thank you which I should have done in last nights post.

I will (hopefully) try again tonight and post again.

Allan

[animal ed]

Well, thanks Gents.
@ Allan
Lap by itself was not good and I was surprised with time - it means that i will push You even more...and did You notice that we are faster with elise than some people with more capable cars. I`m not saying that they are slow but what can produce good and healthy competition!

@ carham

You are not hijacking! If You are - we want to be more hijacked by You!
And I will try to explain what I meant under term "loose" (also believe that Allan would agree) - when present is feeling that car reacts less and slower on input, especially steering.

Regards

[carham]

Hello again,

The discussion in my last post focused on an event (turn #3) in which the car did get "loose", and it did "drift". The question is: are the DIFF set-up changes Allan made, responsible in some way? The Motec data said probably not, since, the event happened on the "coast" side and our changes were intended for the "power" side.

However, the DIFF may have been quick to release under the circumstances (staying on the brakes and 3/2 downshift). The unlock may have been influenced by setting the "pre-load" to 1. :?: Low "pre-load" settings allegedly hasten the DIFF action, and high numbers retard it......how it behaves in GTR2 is a guess which I have found impossible to answer.

There are a couple of other places in the lap where it appears momentary steering corrections may have been made....I have not studied them. So, Allan's general assumption may still be valid. Afterall, he drove the car, I didn't. :-) Next to the stopwatch (like ED says), driver impressions (based on lots of experience) are the most valuable data we have; the objective is to understand them in mechanical terms using the Motec and replay information.

I chose the turn #3 event as one example of how to use the Motec data. My analysis may, at first seem long and time consuming, however, you will learn to perform similiar analysis very quickly (use the curser line and see what things connect).....using your impressions as the going-in guide.

I have added the DIFF channel (user math fuction) and the RIDE HEIGHT scatter plot w/trend lines to help me get quick answers regarding what the DIFF is doing and the instantaneous and overall attitude of the chasssis. No need to waste time guessing. I know, the scatter plot looks like a confusing mess of points, but you can use it with the curser line to follow events through a turn or during braking period, and by using the forward/backward arrow keys one click at a time. You will find that very interesting.

Unfortunately, I have not found a clear method of extracting "understeer & oversteer" information from the GTR2 Motec data......that's where I use the slo-mo overhead replay. If you guys develop a Motec way of doing that, I'd be most appreciative of being clued-in!

Good racing....and lay-off that Turn #2 curb! ;-)
Carham

PS EDIT: Just saw Ed's last post. Yes, a slow reaction possibly followed by an over-reaction is a way of describing a loose condition. A more precise way to discuss the loose/tight condition is the use of the terms: understeer & oversteer... become familiar with their definitions if you are not already used to them. Thanks for the nice comment.

[animal ed]

@ carham

I really appreciate your time and good will to teach us something and I`m offering a little bit better explanation.
I was trying to express feeling with few words but Your short exspression is more accurate. I caught myself that I`m not saying everything - "you know behavior" but what make me do that and why I don`t know.
Second thing - if I describe more accurate loose feeling it would be under influence of my driving preferences besides fact that I`m still discovering my GTR2 driving preference just because of feedback that I`m receiving and that would be only steering wheel FFB - no G-force sensation. So far my preference would be neutral to slight understeering and loose feeling would be to much understeering or general lack of grip. For oversteering I would specify "loose rear".
I will try to avoid that term - only if I`m not sure what`s hapening or for general lack of grip.

Regards

[AllanGP]

Gents

As suspected work is going to prevent me from doing any more laps before this weekend.

I've attached my MoTeC data and .vcr files the 1.22.550 was done with two extra packers (so three clicks on packers from zero) Motec data is timed at 21.49, the second lap 1.22.468 I added one more packer (so 4 clicks up from zero) MoTeC file time 22.45. Hadn't realised an hour had passed:laugh:

The car feels better and as I said it was late at night after a long day so was not driving at my best. I think there maybe more time from those settings but I will also try fewer packers and more ride height as in both cases the suspension is still bottoming. Some days I fire up GTR2 and know I'm going to do good times and sometimes I realise I'm just not "on it" enough to drive like I know I can.

I think I missed the Turn 2 kerbs on at least one of those laps :-D

I did reflect on the fact that just three days ago I celebrated each lap under 1.23, now I think it is average if I'm in the 1.22.5 to 1.22.8 range and a lap of 1.22.9 or above is mentally logged as poor!!

Finally carham I've fiddled with MoTeC and can't figure out how to add the displays you mentioned any chance of a step by step idiots guide on how to add items - your help as ever gratefully appreciated.

Allan

[carham]

We'll work on the definitions of loose, neutral, and tight some more. I read your descriptions and generally agree with the exception, of calling a "pushing" condition as loose......the push is generally referred to as understeer.

Anyway, I watched your 1:22.226 replay...it looked very nice.

My comments:

1.) My overall impression is that your set-up results in a "neutral" with "slight oversteering" on turn entry.......very desirable in most cases.
Turn-in......slight oversteer
Apex.........neutral
Exit...........netral

2.) Turn #3: Beautiful drift going in with a well controlled "neutral" power-on exit. Without seeing the data, I'll give you credit for great technique. ;-)

Otherwise, maybe it could be that the car oversteered unexpectedly going in, and you made a great adjustment. Anyway it looked good.

3.) Exit from turn #6: Car appeared to understeer a bit on exit. You were carrying good speed there and it is a difficult turn.....would need to see data to understand what was happening.

Good lap!
Carham

PS: Good definitions are available on Wikipedia.org

[animal ed]

I forgot to upload data so here it is...19481

Considering corner nr3 - I use to make car doing slight oversteering by entering corner while still on brakes but in this case it was overreaction and i was prepared for that. For neutral exiting I think that my diff setup takes credit for this (60/40/1) but also gave me hard times on nr6 because a lot of understeering (pushing) at that point - or I just missed racing line by beeing to slow on changing direction. Btw - lap was driven with one of my experimental setup. In this case rear was rised much more than front, and diff preload was changed to 5 because I need to understand better how this reflects on driving (I know definition)

Regards

[carham]

Thanks for the Motec data....very interesting.

The data says a stiffer approach and higher ride heights does a better job of keeping the chassis off the track......track hits=6 vs Allan=12. You had no rear hits, only front hits. I would still suggest leveling the car a bit more by raising the front ride height. I still believe a level car will be slightly better on the straights. Give it a try.....maybe less hits and better areo.......I'm curious to see if it helps.

Turn #3: You had same oversteer issue as Allan: brake was on the start of turn-in, weight transferred unloaded RR, DIFF unlocked, RR slowed and lost grip. You made it look very good though!:-) Maybe increasing the "Coast" setting. will stop the RR from losing grip in turn #3?

The DIFF data is very interesting.....definitely locked more than Allan's run and it seems to work for you. Possibly, the DIFF is not as large a factor here.....there is always more to learn. I'm interested in your DIFF impressions.

It's interesting that two different set-up approaches with different drivers yield about the same result....maybe we're thinking too much! However, it does pose an obvious question doesn't it? :laugh: It's no wonder team drivers and engineers argue so much!!

Later today I will post instructions on setting up a DIFF channel and a scatter plot.

Thanks again for the data,
Carham

[carham]

1.) Open Motec.......and open a file.

2.) Click on #6 Suspension screen.

3.) Go to Worksheet bar and right click in Blank area.

4.) Go to Add menue....select Scatter Plot....add the 4 Ride Height channels.

5.) Go to X-Axis....and the Channel Icon...and select the Ground Speed channel.....set the Manual Scale.

6.) Use the Color change and Display tabs to select the channel colors and trendlines.

7.) Calibrate the X axis (0.0 to 6.0in) and Y axis (40.0 to 150.0 mph).

I hope that these instructions will help.

Carham

[animal ed]

My impressions about diff?! Huh! Difficult but I`ll give a try. Increasing value on throtlle give me better traction and more neutral feeling out of slow corners even when one wheel is on kerb (or something) but too much can give hard time when applying throtlle in corner (before exit point) by massive understeering. Increasing value on coasting give me more stabile braking and make easier to enter corner especially if car shows tendency for too much off throtlle oversteering - too much value and I have problem with slow square corners (understeering). Finally preload - I`m still little bit confused about that. If power/coast values are same or simillar - preload is not that important (only for really fine tune) but if there is a significant difference too fast readiness (lower value) can upset car big time by unpredicted movements and too slow transition from power to coast value = offroad (!!) because car reaction was too slow and I was too fast.
And about oversteering...
I made two scatters for oversteering by using math expressions from MoTec. They didn`t work untill I copy them and paste under my math (user) expressions and thus enable editing. As I recall only change was quantity (angle), display unit (degree) and result unit (also degree). Positive values is oversteering (by picking point on scatter it could be visible where that was happened on track map) but I`m confused about negative values - I don`t have that massive understeering!!!!! Maybe with reversing some values under math expression we could get data for understeering and join them in new math expression to get over/understeering in single scatter plot.
On picture upper scatter uses oversteer math for x axis and gyro yaw angle for y axis. Scatter in bottom shows oversteer speed weighted (works ok after editing oversteer math) on x axis and steering wheel angle on y.
I hope this was helpfull.

19492

Regards

Forgot to say - oversteer must be unmarked under MoTec math and marked under yours math...

[Freddyfartbox]

Animal, think of loose as oversteering and tight as understeering. Loose is fast but harsh on tyres, tight is slower but kinder to the car and tyres. That's my understanding anyway.

[edgecrusher]

Keep going, maybe at last I will be able to apply some knowlegde to my setups not only trial and error. Thanks.

[animal ed]

Easy part is to get data from MoTec but to understand them...Huh. Anyway it`s interesting and helps me so far. Carhams approach in analysing data helps much more because of pointing in right direction by describing what we actually read and how it affects on car behavior.

@ Freddy
Your understanding can make you slower than me for one fast lap but you can destroy me over race distance. For one fast lap you need car to be on edge.

[carham]

Animal Ed,

Your post #52 is very interesting. Your description of the DIFF action (1st paragraph) is very good and I see it pretty much the same way. Your comments regarding "pre-load" effects are valuable. :thumbup:

Regarding the "oversteer" calculation in Motec: I'm using version (Motec i2 Pro 1.0) which apparently has no "steered angle" data and therefore, the calculation doesn't work????? I downloaded the 1.03 version last night and ran into problems....need to work on that today.

What Motec version are you using?

And I don't understand what you mean by "marked and "unmarked"? Can you help me a little more?

Thanks,
Carham

[animal ed]

Thank You Carham

I use 1.03.0106 version - last available on MoTec`s page.
Considering "mark" and "unmark" I`m depending on google translate because I can speak well but writing :crying: ... picture can say that better.
Marked
19513
Unmarked
19514

And I forgot about steered angle - this channel is not avalable but "steering wheel angle" is.
19515
Math expression is: smooth(choose('Corr Speed'[km/h] < 50, 0, sgn('G Force Lat'[m/s/s]) * (('Vehicle Wheelbase'[m] * 'G Force Lat'[m/s/s] / sqr('Corr Speed'[m/s])) - sgn(stat_mean('Steering Wheel Angle' [%] * 'G Force Lat'[m/s/s])) * 'Steering Wheel Angle' [%])), 0.2)

Regards

[carham]

Here are the instructions for setting up the DIFF channel report I use:

I report the difference in driving wheel speed: right wheel vs left wheel as a percent (+ or - %). The following instructions will be for a rear wheel drive car. This requires the use of a "User Math" expression.......here's the one I use:


choose('Wheel Speed RL' [mph] / 'Wheel Speed RR' [mph] < 1.0, (100.0*'Wheel Speed RR' [mph] / 'Wheel Speed RL' [mph]-100.0), ((-1.0)*(100.0 * 'Wheel Speed RL' [mph] / 'Wheel Speed RR' [mph]-100.0)))


Positive values signify the right wheel is turning faster than the left wheel, and visa versa, for negative values. Any variety of units for wheel speed are OK.

I set-up this value as a separate channel report under the #5 Transmission tab - General worksheet. As such, it will align the reported DIFF action, along with all the other data, according to track distance and lap time. Additional worksheets can be added for various other reports like, "scatter plots" etc., as you desire.

Detail:

. Open a Motec file channel report screen: go to Transmission Tab-General worksheet (or wherever):

. Click the Tools menue......select: Maths,

. Select: Global/User........select: Add.....enter name,

. Select: Add Expression......then using the expression tools, enter the expression from above,

. Select: Insert Channel......and OK

. Test to see if the calculated data appear,

The reported numbers should range from -100 to +100; remember the calculated number is a percentage. However, in the Math Expression Editor, I've had to use the following to get the values to report correctly:

Display Unit...ratio
Resultant Unit....ratio

Additional Reports:
I have addded an additional worksheet containing a scatter plot showing: the reported DIFF action (Y-axis) vs longitudinal acceleration (X-axis). This plot allows me to quickly, and accurately, determine the operating state of the DIFF (power side or coast side) for any time/location relative to the track, and to view it in context with all the other DIFF data.

I hope the set-up is easy for you.
And I hope you find this tool helpful.:-)
Carham

[carham]

Thank you Animal Ed for post #57! :thumbup: Have a nice day!

Carham

[carham]

Well, I got the "oversteer" math to provide output values that can be shown as a channel report and therefore, used in scatter plots etc. Thanks Ed.

I don't yet understand how the math expression works; therefore, I'm not sure what the output values mean. Until I do, I won't state any observations based on this expression. For example, like Ed, I have substituted the "steering wheel angle [%]" in the calculation without any apparent connection to the amount of actual steering range (degrees to lock), or instantaeous steered angle being used by the front wheels. An output from the expression is produced, but I'm not sure what it means.

It does show a positive value during the slide in turn#3 for Ed's last fast run; for all remaining turns, it shows negative values. I made a very slow lap (40mph) with no "feeling" of either understeer or oversteer; the calculated numbers do not include any with positive values, only "0" or negative values. What do the negative numbers signify?

I will work at understanding this during the next couple of days. :?: :crying:

Cheers,
Carham

[AllanGP]

Well Gents,

I tried a couple of more times tonight to beat Animal Ed's lap - with no joy - but I did definitely discover that (for me) raising the car height does not help.

What I might gain (theoretically) in stopping the suspension hitting the stops, I lose in the feel of the car (even one click up all around) and by two clicks up I'm losing time in The Gooseneck, a little bit in Mansfield and more again entering the Mountain, Hall Bends definitely, the Hairpin and Barn.

In the Gooseneck and Hall Bends the car does not like changing direction at all. In all areas the car doesn't handle the hot rear tires as well as a lower ride height.

During those tests I did try more packers and a bit more rear ARB.

I've kept the Packers & ARB changes, went back to the lowest suspension settings and immediately did a 1.22.488. You can see the lap is pretty scrappy so there is more to come.

With this setting I will try again tomorrow (I hope) and if I make any changes I guess it will have to be more Packers or Spring rates to try and avoid hitting the stops and not ride height.

One more question for carham (if I may); is there a way of telling the best tire slip angle from the MoteC data? I've got a PDF with the supposed best camber angles for all the GT & NGT standard cars in GTR2 (only just found it actually - must have downloaded it ages ago) but frustratingly it does not include the data for the Lotus Elise :-(

Of course then there is the related question of Castor angle (which the PDF doesn't have) but that will be for another time.

Also I'll try and make sense of all the interesting info above - thanks carham ;-)

[carham]

Well Gents,

I tried a couple of more times tonight to beat Animal Ed's lap - with no joy - but I did definitely discover that (for me) raising the car height does not help.....

I've kept the Packers & ARB changes, went back to the lowest suspension settings and immediately did a 1.22.488. You can see the lap is pretty scrappy so there is more to come.

With this setting I will try again tomorrow (I hope) and if I make any changes I guess it will have to be more Packers or Spring rates to try and avoid hitting the stops and not ride height.

One more question for carham (if I may); is there a way of telling the best tire slip angle from the MoteC data? I've got a PDF with the supposed best camber angles for all the GT & NGT standard cars in GTR2 (only just found it actually - must have downloaded it ages ago) but frustratingly it does not include the data for the Lotus Elise :-(......

Ok, raising the ride heights was not the way to go. I hope you go back to your 1:22.242 settings and increase the packers to at least 1/4 inch or more and see if that will reduce the number of ground hits....you are still at 12. Ed has 6 hits with a stiffer car and more packer thickness. Leave the rest of the set-up alone and see what it takes to get the number of hits below 6. Then see what the lap time is and what your impressions are.

Regarding your "slip angle" question....I'm unsure if you're really intending to ask about slip angles since, you mentioned camber angles in the same paragraph (?). I don't think Motec gives us the "slip angles". If it did, the calculation of oversteer/understeer would be very easy. Now, in the 1:22,488 run I did notice the spread betwen the front inboard and out board tire temps is at the high end of the desired range at 10 to 12 deg F.; you could take the camber angles to -2.5 deg. and re-check.

I did see the replay...I can see you're being careful not to run over the turn #2 curb....maybe a little too careful. I know, it's easy for me to say.

I've been investigating the Motec calculation for "oversteer", and I have to say, I'm still not seeing the "forest". :?: I think I've found an addition operation that is mixing units (apples + oranges). :crying:

Hopefully more tomorrow,
Carham

[AllanGP]

Hi,

I'm not an expert (not even a novice in this) but I thought the maximum slip angle achieved by a tire would be influenced by the camber angle used i.e. that there will be an optimum camber angle to achieve the highest tire slip angle? You might have guessed by now I've started reading some of my books!! As they say a little knowledge is a dangerous thing!! Related of course (or is it??) the castor angle must also affect the tyre behaviour and therefore the optimum point at which the tyre gives it's best slip angle. Or more correctly of course the slip angle that delivers the best tyre grip? As my book says this in turn affects the "feel" in the steering wheel and that this feel (the one you think is "right") may not directly relate to the actual point of highest tyre grip?

I hope the above makes sense.

Also you are right by trying to concentrate on missing that kerb I'm not driving that corner as well as before but given the influence on top speed for that long straight I'm just going to practice to drive the corner correctly and miss the kerb - eventually!

It is why I'm am sure this set up will give me 2/10th's (or maybe more Animal :-P).

[animal ed]

Hi,
...

It is why I'm am sure this set up will give me 2/10th's (or maybe more Animal :-P).

Just go for it Allan! :thumbup:

Considering camber and caster - If You use less camber angle which is better for braking, caster can give necessary wheel angle when You turn front wheels. I try to figure that with tyre temps and that`s main reason why I`m using asimetric setup - to play with tyre pressure when camber and caster is about right.

[AllanGP]

Hi Animal,

Good point about a lower camber giving better braking, I never thought about that before. I always added a bit more camber even if it meant a slightly greater than ideal temp differential across the tyre (as carham pointed out) because I thought for hot lapping I'm more interested in cornering power not tyre life??

Anyway I'll include your ideas in my next drive as well if I have time.

I've got this PDF (GTR2 Car Owners Manual NAP) which shows the best camber angle to achieve maximum tyre grip (no mention of Castor angle though). I'd upload it here but the file is over 10Mb and PDF's don't get much smaller with compression. If you want it send me a proper e-mail address via PM and I can send it to you. I think it was from SimLeague.net originally so you might get it there as well - an interesting read.

Apart from the BMW all the Michelin shod cars show the best cambers as Front -3.0 degrees and Rear -2.2 degrees.

[animal ed]

Hi Animal,

Good point about a lower camber giving better braking, I never thought about that before. I always added a bit more camber even if it meant a slightly greater than ideal temp differential across the tyre (as carham pointed out) because I thought for hot lapping I'm more interested in cornering power not tyre life??
...



With tyre temp`s monitoring (inside -outside) You can figure how that same tyre lays on track - smaller difference between=better matched camber and with tyre pressure You can resolve mid tyre temp. When this difference is smallest - You have the best gripp that tyres can give under that suspension stiffnes setup.
Caster - to better visualize... bikes front wheel lays vertically (0 camber angle) to the ground when pointed straight but when wheel is turned left or right - there is an angle!

[carham]

Camber/Caster...another way to think about it:

The physical contact of a pneumatic tire when standing perpendicular, with the track surface, and supporting a given amout of weight, is defined by an area (x sq. inches or sq. mm). This area is called the "contact patch", its size determines the amount of tire rubber material and the track surface material that are available to generate friction. The resulting frictional force is directly proportional to its size and is always in the plane of the patch.

Definition:

The magnitude of the frictional force available from this contact patch is a function of three parameters:

. Patch size.....the larger the patch, the more available force.

. Frictional nature of the contacting materials......coefficient of friction. This coefficient is a function of temperature with an optimium at usually around 90 - 100 deg. C for a racing tire. The coefficient is also a function of the relative motion of the contacting materials...when the relative movement is zero or very small, the coefficient is optimium, when the tire is sliding or slipping, the coefficient is dramitcally reduced.

. The perpendicular or "normal" force (weight) acting on the patch materials. Higher weight yields more frictional force. In the case of a tire, there is usually an upper limit defined by the tire's construction.

Discussion:

Grip: The optimium frictional force can be applied in any direction: rearward for braking, to the side for turning, and straight ahead for accelerating. It can also be used in any combination; however, the vector sum of the combined forces cannot exceed the available maximium. If so, slippage (loss of grip) occurs and the actual friction force is reduced substantially. The familiar Motec "friction circle" under the tire tab shows you how effective your use of the frictional force is.

Camber (side leaning of the wheel): Chassis roll and suspension geometry, when cornering, usually add positve camber to the outside wheels, thus quickly reducing the contact patch area. Adding negative camber (in the set-up) offsets this "roll camber", and maintains the maximium patch area in the turns. Negative camber also adds a small side force; however, the number one objective here is to manage the size of the patch.

The distribution of temperature (outside, middle, inside) across the contact patch provides an indication of how the effectively the patch is being used. Experience says an increasing 6 to 10 deg C linear spread (outside to inside) provides the best overall result. Tire pressure is used to control the center of patch temperature.

Caster (king pin leans back): Positive caster, in the context of this discussion, is a means of providing additional negative camber while turning. It's a functon of steering angle. It's use allows a larger contact patch for straight ahead operation (braking or acceleration) while applying additional negative camber only for cornering. it's effects will also be read into the contact temperatures.

Slip Angle: When viewing from overhead, the slip angle is the angle between the direction the wheel is pointed and the actual direction of travel. When turning, the pointed direction of the wheel is caused to deviate from the true rolling direction, the elastic character of the rubber in the contact patch causes the introduction of a side force, which we call the cornering force. Generally, the relationship between the slip angle and the side force is linear and is proportional to the normal force; however, at some point of higher slip angle the relationship becomes nonlinear and eventaually the side force begins to fall off.

The tire files contain all the coeffiicient and slip angle data.

Oversteer/Understeer: When a car travels in a curve for example, the rear wheels also operate at a slip angle. The relative magnitudes of the front and rear slip angles define if a car is understeering or oversteering. When the front is larger, the car is understeering, and its oversteering when the opposite is true. The car is defined as neutral when they are equal.

You guys probably know all this already :-) so I apologize for a long boring post.
Carham

[Freddyfartbox]

To analyze a lap the way you have done would require the Motec data, right Carham? I'd love it if you could look at my Porsche GT3 RSR lap of Cadwell in that amount of detail, but getting to the stage of having Motec data of my laps has eluded me so far (ie, total noob.)

[carham]

To analyze a lap the way you have done would require the Motec data, right Carham? I'd love it if you could look at my Porsche GT3 RSR lap of Cadwell in that amount of detail, but getting to the stage of having Motec data of my laps has eluded me so far (ie, total noob.)

Freddy, yes the Motec data are very helpful....first off, its the only source for knowing g-loads and temperatures which are nessasary for understanding what's happening on the track. Can you decribe the difficulty? There are several people here who can assist you. Have you read the "motec install" posts?

Cheers,
carham

[AllanGP]

Carham,

Another excellent description of what I was thinking about - thanks.

Freddy,

For MoTeC use read all of this thread;

http://www.nogripracing.com/forum/showthread.php?t=13657

[AllanGP]

Well Animal,

Over to you once more :-D:-D:-D

Not the greatest lap ever (nearly illegal in 2 places, but at those points also losing time :laugh:).

I've included in the attachment another lap at 1.22.208 just in case you don't like my 1.21.982 one :-P

I was sure this set up had more to give and in fact four times before that I was on for 1.21's but lost it in The Mountain to the Finish line.

So far I haven't touched the Packers or Spring Rates - so maybe more to come yet :mrgreen: Still hitting the tarmac 12 times !!

I simply refined my front tyre pressures and cambers all around and again I have not explored all possibilities yet.

Let me know what you think of it.

Carham, didn't hit the kerb in turn 2 and I am carrying more speed at the Hairpin as well - it all helps.

[animal ed]

Allan

In tennis when ball hit the line they call it "in" - Your lap is OK.
Now back to Cadwell just when i start to enjoy in good setup for AMS Renault track.

[AllanGP]

Hey Animal,

Just think of all the times I've had to come back to Cadwell because of you :-D

I might get a chance to try the Lambo around here!!

[carham]

AllanGP 1:21.982 Lap:

Congratulations, this is a very good lap. There is not much I can suggest after reviewing the replay and Motec data. :thumbup:

My feedback:

Handling appears about as "neutral" as you can get it. The replay (overhead camera) data showed a great line all the way through from turn #1 to Turn #5. You appeared agressive and accurate with generaly good control. Instead of sections with understeer or oversteer, there were areas where the car would be in a neutral looking drift. Add that the Motec traces showed no "surprising" yaw deviations or steering corrections, I conclude that the car handled extremely well.

Maybe the stiffer rear rollbar (86) was a very positive change (?).

Other than taking out a little front camber, and adding a "bunch" of packer thickness, there is nothing in the data telling me to make any changes.

If you haven't done so, I encourage you to add the DIFF channel and the ride height scatter plot you your Motec tools.

Looks likes you have good set-up that suites you.......the rest is up to driver! ;-)

Carham

PS: I've enjoyed working, and learning. with a couple of great drivers......and I look forward to doing it again. I'll keep working on a Motec way to quantify oversteer/understeer; keep your ideas coming.

[AllanGP]

Carham,

Thank you very much, certainly the first part of the lap was good and the finish also.

I'm going to try your ideas as they were next on my list anyway.

It has been and absolute pleasure have your help and I shall certainly be modifying my MoTeC as you say - may involve a few more questions when I try to do it ;-)

I'm going to do a Lambo lap soon and post the data but we have taken up so much of your time already if you don't want to look at it no problem - it is about time I learnt to do it myself anyway - can I assume the principles are the same - i.e. do the diff ideas (for the same track) apply to all cars?

Once again you are a star man.

Allan

[carham]

Allen,

In your original PM, you asked me to review your Motec data and to "offer some insight". In my view, providing insight includes demonstrating a process of analysis using the available data that will help you make productive set-up changes. I believe I have done both for you and I've enjoyed doing it.

The available data include: the lap time, your driving impressions, the replay information, and lastly, the Motec information. The "process", as you have seen, simply involves anwering two questions:

. What did the car do?
. Why did the car do that?

Getting those answers, requires a bit of detective work (connecting the dots). I agree, it's helpful to have some automotive experience; which you have. Motec is a large help in answering the second question......it provides many of the important dots! I've added two additional sources of dots: 1.) The DIFF user math, and 2.) the ride height scatter plot.

The DIFF function effects how power and momentum are distributed through the two driving wheel contact patches. There is some debate as to it's relevance in GTR2; my feeling is that I would rather look to see for myself than to guess. With the data, you can make up your own mind. Example: It provided an important clue in the chain of events as to why your car oversteered going into turn #3.

The ride height scatter plot dosen't really add data, rather it organizes all that information into a format providing an instant "big picture", while at the same time, allowing a simple way of studying events in sequential detail by observing the changing orientation of the car as you "click" (right arrow forward in time/left arrow backward in time) through an event: like braking down for a turn, or negotiating the entry and exit of a turn. You can watch how vehicle weight is being transferred from wheel to wheel moment by moment in a much clearer way.

Thank you for allowing me to use this this thread to convey some ideas. ;-)

It has been fun! :-)
Carham

[AllanGP]

Carham,

Again many thanks for all your help and insight.

I've added the Ride Height Scatter Plot without too much difficulty.

I've added the Differential Calculation, again no real problems except that the range on my "graph" has a centre line of 1 and the plot (due to the values from my quickest lap) is in the range 0.75 to 1.30.

I guess I've missed something about setting the scale somewhere?

Under Channel Properties the Quantity is "Unitless" and under "Settings" the "Unit" is None[]

Cheers, Allan

Doh, realised after I posted I used /100 not -100 at the end of your expression - now all okay - thanks again - Note to self: don't do math late at night after a few glasses of wine!!

[AllanGP]

Carham,

I have three more questions for you;

1) If we got one of the track builders to build a very large circle of tarmac, with say a white line at 50ft, 75ft, 100ft, 150ft, 200ft, then if we drove a car at a maximum speed achievable for each diameter, using various Camber Settings, could we not then see in MoTeC the set up giving maximum lateral G and therefore determine the best settings? Just a thought.

2) You mention looking at the .vcr's in super slow motion, how did you do that?

Finally;

3) This is a real NooB one, how did you get things like the ride height scatter plot as a jpeg file? Mine doesn't even want to copy, let alone paste anywhere (and even then it would not be Jpeg format?)

I can "Print Screen" and paste it into Power Point but jpeg's are simpler for posting??

Cheers, Allan

[animal ed]

I will take liberty for answering on 2 and 3 if you don`t mind. On first one I also like to hear answer.
2) It`s simple - just press and hold 0 (zero) on numeric part of Your keyboard while watching replay. Other "zero" (above letters doesn`t work) therefore I can`t watch slowmo on my laptop.

And third - when you use "print screen" (ctrl+print screen) paste it in ms paint (part of windows) by opening tab "edit" - paste option is available then save in whatever graphics format You like(first given choice is bmp)

Cheers

[carham]

Question #2: Correct, the "zero" key in the "number pad" provides slo-motion. However, the decimal point key "." provides the "super slo-motion". I use all three. I will press the "." key and simultaneously "zero" key to quickly change from one to the other, or simultaneously use the right or left arrow keys while holding the "." to go forward/backward quickly.

I use the overhead camera at all three replay speeds. It takes some interpretation, but if you study how the front and the rear are behaving you can pick up the clues for oversterr/understeer.....many times it's obvious. When these clues are not present, the car is probably close to neutral. In many cases, a quick check of the Steering and Yaw traces will correlate with bulges in the yaw curve and opposite steer corrections. Once you confirm the behaviour, then look for the cause.

Note: The the reported time readings in the replay correlate exactly with the time values shown on the traces.

Question #3: I use Microsoft Digital Editor, otherwise same as Ed. Also, if you use (Ctrl & Alt + PrtScn) you will capture only the one widow that is in the foreground.

Question #1: Yes, that would work. A "skid pad" was, and I guess still is, a commonly used tool for suspension development. It was famously used by Jim Hall in the 1960's for development of his winged and "sucker" cars. He actually had one constructed on his ranch in Texas. Computer simulation and sophisticated tire testing machines may have diminished their use in the real world. On occassion, I will take a car and set-up for a certain track to another track where I can test for a specific issue and retrieve the Motec data.....for example, I have used the long straight at Nords for fine tuning aero considerations. We should look for a place that has a long 180 or 270 deg. level sweeper with a long straight preceeding it.......that might do as a place to test.

I think your about to get serious about this! :laugh:

Carham

[AllanGP]

Hi Ed/Carham,

Deadly serious, never started anything without the idea of being first :-D - doesn't happen very often but nobody has ever faulted my determination!!

I will post a request in the "tracks" forum and see what response I get - maybe some of the other guys will chip in to say +1 and see what happens. I suppose we would need multiple circles with ranges of tarmac co-efficients and known ranges of bumps - we could build our own digital track test facility like MIRA here in the UK (where I used to go testing prior to a new season). We will also need a method of getting our bearings on a large circle - that one will need some thought :-) Maybe a centre "lighthouse" and Armco all the way around at 500ft with arrows on the ground pointing to the lighthouse (I suppose unlike our road white lines they could give the "white" lines the same co-efficient as the road surface so you don't getting false results when circling (you see I am serious ;-)).

Edit: Made the post now so start supporting it :mrgreen:

Well I never new paint was that sophisticated must be 10 years since I last opened it up.

Slow Motion info - great - I wondered if it was going to be easy or if you had some clever video stuff like Fraps.

And just to prove I am learning - see attached - need to do something about that Lambo Ride Height/Spring Stiffness/Packers!!

[carham]

Allan, good. I think you'll find it visually helpful if you add a linear "trendline" for each of the ride height channels. The trend lines represent the "averge or mean' trend with car speed. Use them as a quick refernce showing you the average differences in the four ride heights over the speed range. I color coordinate the trend lines giving each it's own color.....red/pink for the fronts, dark/light blue for the rears. Do what works for you, but if we all adopt a standard format, it will be easier to compare each other's data.

My impression of your plot says that the car appears level on average, but too low....see all the track contact points.

Carham

[AllanGP]

Carham,

Added trend lines and changed colour combinations as you suggested!

There is a danger I might be beginning to understand this :-D

Allan

[carham]

OMG, you're morphing into an engineer! :ohmy: :-)

Note:

. Change the scale of the "Y" axis to.....0 to 220
. Change the scale of the "X" axis........so you can see the top speed.

Here's what I immediately see:

. Trend lines being grouped together show car appears "level" through most of the speed range. Good for minimum body drag. If car has an underbody downforce system (splitter-flat center-diffuser exit), as you know, it usually works best if car remains level and low. The game files actually contain statements that increase/decrease drag and downforce effects as a fuction of pitch, height, and speed. These effects usually apply to all GTR2 cars, varying with car type. The underbody effects may be good enough to allow for smaller wing settings(less wing drag). :thumbup:

. Trend lines with very little downward slope show that areo forces don't change the car attitude, or height, much with speed (re-check after scale change). Spring forces may be high in relation to the aero downforces. That may be OK, or possibly not, i.e., if the chassis is stiff, less front dive during braking with less front camber change (less loss of contact patch) and possibly better front grip.

. Data points hitting "0" in several places throughout the speed range (from 45 on up), suggests the static ride heights may be too low. Increase front and rear by equal amounts. Bottoming out generally subtracts kinetic energy.

End of lesson for today.

You should now expect your knowledge to grow linearly, and your driving ability to deteriorate exponentially......too much studying, not enough driving! :laugh:

Carham

[AllanGP]

Carham,

And lo, it was done!! :laugh:

Many thanks for yet more useful insight, I may even get to try driving tomorrow!!

Allan

[AllanGP]

Actually, I managed to get a few laps in tonight.

My best time ever in a GT car at this track. Still 4/10ths off Animal's time, that I think should be fairly easy as the set up is not right yet.

Not sure about the first time 1.11 looks way too fast, I'll be happy if I stay ahead of Animal :-)

My thoughts;

Still need work on ride height too many 0's. However I've gone stiffer all round and the (front in particular) tyres are now not warming up properly. Might have to try more height and less spring rate? Unlike the Elise raising the height so far is not having a detrimental effect on the handling.

Could try more packers but already using quite a few??

Understeer looks okay? Had a quick look in slow mo but not an expert on this by any means.

Back end still "loose" even though I've added some rear ARB - may be could do with more but I read some where front to back ARB should be 4:1, and I was thinking of lowering front ARB to get more heat in the front tyres?

No idea if all the above makes sense - at the moment it is mostly what I "feel" is right - although for sure the Ride Height graph is a big help.

Anyway that is it for today, should get a chance to try again tomorrow.

[AllanGP]

Carham,

I downloaded AutoSimSport Volume 2 Issue 10 from here;

http://autosimsport.net/backissues.php#vol2

Two great articles about GTR2 physics;

p24 GTR2 - The Ultimate Guide

p34 Split Second

As we know the "standard" physics is not perfect and this might help in choosing Set Up directions??

A have a more detailed PDF with more data than in the article on p24 but it is too big to upload - if you are interested I could e-mail you a copy (sent a copy to Animal a few days ago). I know realise the info relates to their GTR2 modification the "NAP mod" but interesting nevertheless.

Allan

[AllanGP]

Okay Animal,

Now you have two times to beat :clap:

Still not happy with the front tyre temp and as you can see not a great lap, so even with this set up I think I can go quicker.

However, for now over to you :laugh:

Attached Data

Hopefully I'll get a chance to tackle another circuit before you beat me!!

Allan

[animal ed]

Not this time Allan! Not with GT`s! :devil: This lap was all about keeping the car on the road no matter how fast will it be.
Setup - I don`t know what to say. :?: I called him "start" but barely deserved that name. Considering elise - I`m really stuck with it! Four lap stint, best lap 22:25x, worse lap 22:400... I think that I need little bit off Cadwell/elise to charge batteries... but I`m not giving up! :mrgreen:

19681

add
Considering link that You gave us for autosimsport... Did You try NAP mod? I did and I was that much impressed that I made separate install of gtr2 just for this! I`m definetly slower but have more fun!

[AllanGP]

First of all well done in the GT but I can go quicker, so this should get interesting!

No, never tried the Mod it does sound like the physics would be more realistic but for Hot Lapping at No Grip we will have to stick with the standard install and work out how to go fast with that - even if some of it is contrary to proper racing set up theory.

Anyway I've barely got time to do GTR2 let alone consider anything else, although PnG will get some attention once they create the Hot Lap section :-D

I've run a few laps at AMS Renault (nice circuit, very smooth), so I think I will post a couple of times there before taking on your GT Cadwell time - a GT a Cadwell is pretty manic - it took me quite a few laps to re-calibrate my brain from driving the Elise.

Also I'm getting deeper and deeper into the analysis thing, which is also taking time (and occupying one of my two brain cells :crying:)

Have you supported our Tyre Circuit yet??

[animal ed]

No, never tried the Mod it does sound like the physics would be more realistic but for Hot Lapping at No Grip we will have to stick with the standard install and work out how to go fast with that - even if some of it is contrary to proper racing set up theory.
This is the reason why I have another "experimental" install of gtr2... for friendly competition I have clean game only tracks added - no mods!


...and occupying one of my two brain cells :crying:


Hey! This is not fair! I have only one! :laugh:

...Have you supported our Tyre Circuit yet??
Going to do right now.

Considering GT laps - I can also go way faster so I`m waiting for Your responce...:thumbup:

[AllanGP]

Animal,

Not much faster but even hundredths count :-D

Over to you!

Allan

[animal ed]

Yesterday I had edgecrusher "medicine" (job problems) but with opposite result on hotlaps. I couldn`t get together ONE SINGLE LAP!!!!!
Probably I was also in a bad mood when I told that this lambo setup doesn`t deserve to be starting point... only change was rear springs soften by one click and real attack on second flyer because front tyres is not warm enough and pushing only get you too big difference between front and rear tyre temps for every other lap in this stint.

Here You have also my setup for AMS besides Motecs for both Cadwell and AMS...

19737

[AllanGP]

First of all well done, I think there is more time to come from my set up, whether it will be 4 tenths is another question.............

I don't know about you but I think I understood most of what carham said on the Elise but I'm really struggling with interpreting the MoTeC data for the Lambo.

Then when I look at the data from AMS (which is probably as far away from Cadwell as you can get, open, smooth, flat) I have simply no idea where to start. Ride Height is easy because it is so smooth and flat but Diff I'm not sure about, added quite a bit on "Power" and gone quicker but I might have gone quicker anyway as I learn the circuit.

I really thought I was getting somewhere with MoTeC and set up but now I'm not so sure. Anyway it was always going to be a long haul - as I said to Carham a Winter project (hopefully only one Winter :-D)

I've been working my way through the GTR2 MoTeC i2 Pro Beginners Guide and many of the screen shots in there do not exist in my MoTeC set up. Page 26 (Weight Transfer) and page 27 (Oversteer) look particularly useful. So I am trying to work out how to set them up in my MoTeC. I think you need the full set of tools to make proper progress with the overall Set Up - every change in one setting affects the other ones, I guess the combinations are some what more than getting the right lottery numbers :laugh:).

Anyway I shall try and beat your GT time (at Cadwell) at some point but I see I need to go a bit quicker in the Elise at AMS Renault now - it strikes me that this is a circuit where once you know it, the time will drop of quite quickly.

[animal ed]

First thank You. I`m sure that You will find more than 4/10.
About interpreting lambo MoTec data - bare on mind that you look at completely different animal data. Bottoming is not crucial in terms of losing top speed because of powerfull engine but it`s important if You went off racing line because of bottoming and losing grip. In real life racing it`s much more important because of possible damaging underbody among the other reasons.
Diff settings - I`m still experimenting with but things that I know - higher value on power = better traction out of corners especially if rear wheels are not on same surface (left on tarmac and right on kerb or grass) but it`s much more important for cars able for powersliding - no need for TC that much. On diff plot that You made it`s very notable that on "coast" is diff much more active therefore I think needs more attention. See on data where on track is diff very active and try to recall (untill we get :-Dor find :-)or make :mrgreen:right oversteer math) did You have problems with happy tail which makes You unhappy. If You had = increasing value could solve problem.
Preload - how fast would diff switch from power to coast value (and opposite). Higher value = slower switching from one mode to other. My opinion is that "slower" preload is better for soft suspension setup.
For AMS setup - just start with something that You know. Smooth track, high and mid speed sweepers... low and soft setup is good starting point. With aero - try opposite solutions and see is it better to have higher top speed or better corner speed (or something between)...

I hope this helped.

[AllanGP]

Hi,

Thanks I'll try your ideas.

Re: Oversteer Math; in the "GTR2 i2 Pro Beginners Guide" it clearly gives details on an Oversteer sheet (page 27 of manual). If you haven't got this pdf I can e-mail it to you.

Plus if you look at the Channels tab, left hand side of screen in MoTeC, right down the bottom there is already an "Oversteer" channel and a Oversteer (Speed Weighted) channel - I think you can use those?? That seems to be what they refer to in the Beginners Guide.

Finally have you ever looked at the MoTec demo video - under the "Help" tab - it really is quite good with tips on how to change your views of data.

You never know I may even get a chance to drive tomorrow :laugh:

As Carham said as your analysis knowledge goes up your speed comes down :crying:

[animal ed]

I think that I finally get oversteer math working properly! :clap:

First under math add constant called "steering wheel lock" in degrees but tricky point is that this constant needs to be same as in game. Different cars - different lock but most ocassional is 15 deg by default.
19755

Than add math exspression called Steered angle just like this:
('Steering Wheel Angle' [ratio] * 'Steering wheel lock' [deg]) / 100

19756
After that original MoTecs math expression for oversteer works but data looks really scary (at least in my case) if you use just garph or scatter plot. Combining oversteer and steering wheel angle (but not ratio - must be percentage) in time/distance graph have much more sense...

19757

...and thank You Allan for pushing me to think again! :thumbup:

[AllanGP]

Hey Animal,

Well done - I will try and set this up on my MoTeC tomorrow.

I'm guessing you have the "Beginners Guide" as the thing it says in there is that both steering wheel locks must be the same figure for it to work properly.

I'm also going to start using Tim McArthur's Set Up Development tool, to see if that helps as well.

Allan

[AllanGP]

Animal,

Added a Weight Transfer Sheet no problem. Although I see in your User Maths you have set up a Front Ride Height and Rear Ride Height expression, I take it they are just Front Right + Front Left/2? etc. Can't see the end of your expression from the screen shots?

More importantly, I've done the Oversteer Worksheet but get no numbers, I've added the Steered Angle constant, still no joy - can you look at the screen shots and see if you can see what I have done wrong? Is it something to do with Units as my expression is Unitless currently?

Post some screen shots if you can.

Cheers, Allan

[animal ed]

No, no! Constant is steering wheel lock - not angle! And new math expression is steered angle! Than You can delete oversteer under user math and copy it again from MoTec math but with no changes - in this case You don`t need to change source (no matter if used from Yours math or MoTecs in graph but propper must be marked under math).
Math expression is (copy that and paste after You add constant):

('Steering Wheel Angle' [ratio] * 'Steering wheel lock' [deg]) / 100

...and it must work if right path for math expression is chosed (Your math or MoTecs)... just in case - mark both under math expressions.

For weight transfer - I was trying to figure that by longitudinal chasis movements but not as G force therefore I use math expression for front hight:
('Ride Height FL' [mm] + 'Ride Height FR' [mm]) / 2

... and for rear:
('Ride Height RL' [mm] + 'Ride Height RR' [mm]) / 2

...also simillar for suspension position and result is this:
19765

[AllanGP]

Well Mate,

I think I'm being a bit thick here but I have done what you said and still no result.

See my screen shots.

I'm convinced it is something to do with the fact that in the Right hand column under channels the "Oversteer" component shows N/A but I've no idea how to sort it.

Can you post the screen shot of your Maths expression in Edit Mode and I can see exactly what you have done??

Cheers. A

[animal ed]

Ok. Try this way:
On first picture: step one - add constant named "steering wheel lock" expressed in degrees.
step two - add math expression named "steered angle" but You must define how it will be expressed (picture 2).
On third picture is original math expression which now work after You add math for "steered angle" but it can be showed only if right one is choosed for graph or scatter (graph or scatter properties - F5 button). Just in case - delete copy of changed (by my previous instructions) MoTec math for oversteer and copy again original, place it under Your (user) math with no changes...

19771

19772

19773

19774

[AllanGP]

Hey Animal,

Star man, it works!!

:thumbup::thumbup::thumbup:

Allan

Now to understand what to do when the range is beyond +1 to -5??

Maybe Carham can help us with one of his fine tutorial posts (I hope) ;-)

[animal ed]

Finally I catch time... just to make it easier create new graph like this:
On menubar - Layout - new worksheet (name it whatever You like). Next step is to create time/distance graph, add channels in same group: oversteer and steering wheel angle (You can also add throttle position and brake pedal position in different groups like I did). Steering wheel angle should be expressed in percent and it looks like this.
19837
Oversteer line below zero actually shows understeering and above zero is oversteering. Ideal oversteer line would be flat but world is not ideal :crying: and also oversteer line (if it is - You didn`t push car to the limit) so You need to see where that over/understeering happened - for "why" I need someone smarter than me to answer that. In that graph You can see what was Your responce - does it bother You or not and with throttle and break in graph it`s visible in what conditions happened curved line on oversteering graph. Considering values in numbers - higher number=bigger problem.

Cheers
19839
19838

[carham]

Hello again......been traveling for the last week without a computer, so I sort of got out of touch for a while.

I have said, that until I fully understood the "Oversteer" math calculation, I would refrain from commenting about it. I now believe I understand it's definition, it's derivation, and the mechanics of the "sgn" control variable. I'm not sure this math expression exactly reflects the formal definition of these characteristics; however, I suspect the output correlates reasonable well and, will therefore prove useful.

Like you, I calculated a "Steered Angle" value using the constant "lock" value. My channel report for "Oversteer" shows the value in "degrees".

My current understanding is that the oversteer expression, calculates either: the sum, or the difference, of a calculated vehicle direction and the "Steered Angle", depending on the "sign" value (direction) of the lateral acceleration. It reports a (+) output as oversteer, and a (-) output as understeer, with the quantitative value being proportional to the severity of either condition. The output calculation includes a "smoothing" operation which sort of averages the values over 0.2 sec. intervals as it proceeds through the lap data.

For vehicle speeds less than 50 (km/h), the output report is "0". For Lateral G's =0.0, the output is also "0". I currently show the channel report on a "Steering" worksheet under the "Driver" menue.

At this point, I would suggest (if you're interested) we compare our output values as a means of calibrating against each other, resolving any differences before filling this thread up with a bunch of values:

I suggest we use Ed's (1:22.226) run from Cadwell Park with the Elise. Here are mine: :-)

Oversteer......9.9104 deg. at (0:28.190 sec.)

Understeer.....-5.0595 deg. at (0:41.113 sec.)

Cheers,
Carham

[animal ed]

First - I`m glad You`re back! :-D
Second - I think that we are talking about my lap (1:22:226) and, if I`m right, we have different values:

6,7659 degree at 0:28:190 (oversteering)
-2,5651 degree at 0:41:113 (understeering)

I use original MoTecs math for oversteering (no changes) constant for steering wheel lock 15 degrees and math for steered angle:

('Steering Wheel Angle' [ratio] * 'Steering wheel lock' [deg]) / 100

but result unit of this expression is in radian (like original math for oversteering requests).

Are You use degrees for steered angle math?


ADD
Oversteer (speed weighted)
9,1218 at 0:28:201 (couldn`t place cursor on 190)
-5,1855 at 0:41:113

[carham]

Hi Ed,

Sorry about the lap confusion...I made an edit to my last post....thanks.

I see you added new values (speed weighted oversteer) which are closer to the ones I reported. I'm not sure what these results indicate at the moment, but it's encouraging that our numbers seem to be in the same ballpark. :thumbup:

I am also using the original Motec math for the Oversteer calculation. My Steered Angle expression is the same also, except that mine uses [deg] for the Steering Wheel parameter units. For some reason, Motec won't let me specify [ratio] like your does. I tested my calculation (see attachment: Test-Full Lock) and confirmed that I'm calculating a correct value for the Steered Angle. In the Oversteer calculation, the units used are [radians] so, I think that is all OK.

The first two attachments show my math expressions for: Oversteer and Steered Angle; the last two are Motec channel reports showing the pertinent data for times: 0:28.190 and 0:41.113.

I'm not sure what the next check should be.....http://www.clicksmilies.com/s1106/fragend/confused-smiley-013.gif

lol,
Carham

[animal ed]

No problem Carham. Allan have fastest time :-( but I have better "reference" lap (all kind of mess ;-)).

Speed weighted is also original MoTecs math expression (attachment) and for steering wheel units as I recall - before You make math expression steering wheel angle channel must be changed to show values in ratio on graph or scatter which is allready in use. After that when You are inserting channel in math expression it can be shown as ratio.

[AllanGP]

Hi Both,

Well my Oversteer calculation is the same as yours Carham and I guess Animals is too as I got it from him!!

The MoTeC guide says this about the function of the Oversteer calculation;

"In order for this worksheet to work correctly it’s important to make sure that the steering lock figure in MoTeC is the same as the one used for your in-game setup.

By default this is set to 15.0 degrees. To adjust it in MoTeC select “Tools- Maths- GTR2 Analysis- Constants- Steering Lock and click Edit”.

Oversteer is displayed as a positive value, Understeer is displayed as a negative value.

This trace calculates the difference between how much steering lock you apply for a bend and how much steering lock you would theoretically expect to apply for the same corner.

The aim is to keep the values as close to 0 as possible. In practice so long as it’s within the -5 to +1 range the car is probably handling reasonably. This is just an indicator and should be used along with the other traces to get a picture if how the car is working."

I'll look at my figures for Animals data later as tonight is a "driving" night :-D

Carham, any word on the permission to modify Willow Springs?

Allan

[AllanGP]

Well Animal/Carham,

I've loaded Animals MoTeC data and my values are;

At 28.190: 6.7615
At 41.113: -2.5651

Obviously I'm not using Speed Weighted Figures.

BTW Animal, if you have a wheel mouse you can zoom into the data until the left/right arrows with one press moves 0.001, then zoom out again to look at the graphs at the exact point you want to. Or you can extend the green bar on the lap indicator for the zooming effect.

Allan

[carham]

Allan/Ed,

Based on you results for oversteer, the ball seems to be in "my court" to explain why my results are different. It would be helpful if you guys could provide me the following data (from your calculations) at the (0:28.190) point:

Steered Angle....w/units
Corr Speed........w/units
G Force Lat'.......w/units

See my attachment from above. Just the numbers....no need for the plot.

Thanks,
Carham

[AllanGP]

Hi,

Steered Angle -53.64 w/units %
Corr Speed 67.6 w/units mph
G Force Lat' -1.746 w/units G

I have a daft additional question for you both. My son (James, aged 9) asked to have a go at GTR2 tonight :-D:-D I've set him up in Novice Mode but the In Cockpit view doesn't show the HUD and if you toggle the Insert key it does show the HUD on the Bonnet view but not In Cockpit. I've got no idea how I set mine up originally, any good ideas??

Cheers, Allan

[carham]

Hi,

I have a daft additional question for you both. My son (James, aged 9) asked to have a go at GTR2 tonight :-D:-D I've set him up in Novice Mode but the In Cockpit view doesn't show the HUD and if you toggle the Insert key it does show the HUD on the Bonnet view but not In Cockpit. I've got no idea how I set mine up originally, any good ideas??

Cheers, Allan

If your son is racing under his name, he will have a (James.plr) file. Under "Graphic Options" find these lines:

HUD="1" // 0=none, 1=Full, 2=Minimal (when enabled)
Minimal HUD="1" // Whether minimal HUD is included when cycling through HUDs
Minimal HUD Position="2" // 0=left, 1=centre, 2=right

Set HUD ="1". Maybe that's what you missed??

Carham

[animal ed]

Carham/Allan

Here is my data
Steered angle........-0,0805 / rad or -4,6101 / deg
Corr speed...........108,8 / kmh or 67,6 / mph
G force lat..........-1,746 / G

...and for visible HUD in cockpit - go to options in game than advanced - first choice in middle column...

[AllanGP]

Thanks Guys,

Game Options/Advanced as Animal said was what I hadn't done.

He's 1.17 at Snetterton in Novice Mode - not bad for a start!!

Edit: Now 1.15.2!! This was by 2.30pm today.

Edit 2: Now 1.11.9 @ 5.00pm today (with a two hour break!) Looks like I might be in trouble and have to practice more :-D

Allan

[AllanGP]

Well I have been trying to apply some of my knowledge at Cadwell with the Lambo. Not quite as quick as you Animal but a bit closer and I think without changes there is a bit more to come yet.

I could do with getting the front tyres warmer and have switched to mediums at the rear.

Not sure but think the diff could do with a little tweaking and need to spend some more time on that.

The few "bottoming's" in the suspension are at obvious places and I might try more packers, even though I'm already using 0.7 inch +

Anyway the data is here if you want to have a look.

[animal ed]

Allan

It seems that Your elise time under 1:22 is in real danger. Still need to find little bit more than 1/10 but I`m close. In my motecs You will find two faster laps comparing to this uploaded but slower one (089) was god and faster (059) was across the line. Shame that laps was in same stint therefore faster was recorded but I was curious will it be under `22...

[AllanGP]

Hey,

Well done. I'm sure you will beat my time and then I'll be back to Cadwell :-D

Not had a chance to look at your MoTeC yet but if you beat my time it will allow me to try out some ideas I've had on the set up I used for my time.

Allan

[AllanGP]

Well I have a MoTeC question for you (Animal) and Carham.

If you look on Spads MoTeC thread, in GTR Evolution section, you will see he has a graph for the Dampers that has the vertical axis as "Time" in my MoTeC it comes up as %. Clearly both are recording the same data with a different formula.

So my MoTeC shows;

http://www.nogripracing.com/forum/attachment.php?attachmentid=20190&stc=1&d=1252441742

And you can see that you have the option to look at the Maths Formula;

http://www.nogripracing.com/forum/attachment.php?attachmentid=20191&stc=1&d=1252441742

But in Spads the same MoTeC data looks like this;

http://www.nogripracing.com/forum/attachment.php?attachmentid=20192&stc=1&d=1252441742

But in this case you cannot access the Maths Formula;

http://www.nogripracing.com/forum/attachment.php?attachmentid=20193&stc=1&d=1252441742

Any good ideas? Do you know what he might have used, if you read the thread even he is not sure because he thinks it came from an earlier install of the MoTeC programme?

Also in both cases what is the data actually telling us??

Allan

[animal ed]

Reason why Spad`s hostogram use time instead percentage is because of using standard histogram instead suspension histo. In that case You can choose how y-axis will be expressed. There is no math for this - only channels and seems that he didn`t do any new math expressions or MoTec use Your math no matter of different project (not likely but possible)...
And what this data telling us? :?:
From this data we can see in what damper speeds is most action. Is it on bump or rebound, slow or fast. If You have more slow speed samples there is no need to play much with fast bump or fast rebound suspension setup in garage - car will more react on slow bump and rebound settings changes. I think...and maybe I`m right.:-)

[AllanGP]

Hi,

I think I understand what you are saying but how do I switch my histogram to look like his?

I'm trying to build up my MoTeC into a set of screens in the layout I want and I'd like to include this.

Cheers.

Plus there are a few people in the GTR Evolution thread who want to know this answer as well and once I get it I can post a reply there, with credit to you of course :-D

Update: Actually I think I've worked out how to do it - leave it with me for a few Hours.

Allan

[AllanGP]

Animal/All,

Sorted it.


http://www.nogripracing.com/forum/attachment.php?attachmentid=20343&stc=1&d=1252869566


I will write up a little "How to" in the next couple of days and post it here for you to give it a "peer" review before posting it in Spads thread.

Allan

[animal ed]

Allan
I think it`s Your turn to take elise out of garage!:clap:
Again faster by fraction (0,06) ... I`ll ad MoTec and setup later...

Cheers

[AllanGP]

Animal,

Well done. Looks like more work at Cadwell for me :-D not a problem. I love that circuit.

I wonder how long it will take me, not driven the Elise since I set that lap back on the 15th of August.

I've got some GT work to finish first and I've scrambled my brain trying to understand the MoTeC data.

So it could take sometime.

Allan

[AllanGP]

Carham,

I think I got it.

You use the same formula for both displays, as per attached?

100.0 * 'Wheel Speed RR' [mph] / 'Wheel Speed RL' [mph] - 100.0

http://www.nogripracing.com/forum/attachment.php?attachmentid=20781&stc=1&d=1254260926

http://www.nogripracing.com/forum/attachment.php?attachmentid=20782&stc=1&d=1254260804

Allan

[carham]

Allan, attachments look correct.

Carham

[AllanGP]

Cheers,

I will start the "How to................" and once I've got the easy bit done we can chat about the interpretation bit!! I'll put what I understand down to start with.

Likely to be next week though as I'm off to Scotland on Friday (old school reunion!!) and any spare time this week I need to try and beat Animal Ed :banana:

Allan

[carham]

Have fun at your reunion......on Saturday I'm attending my 50th high school reunion back in Wisconsin. :-P

Time marches on!
Carham

[zuhairreza]

ok guys so I was reading this thread, lots of useful information. May I know one thing, what mode are you guys playing on? Novice? Simulation? And, are all aids on or off? I will try to record/better my lap times. :D

[animal ed]

No aids except auto clutch because I use momo racing wheel - no clutch. I`m also sure that Allan is on simulation.

[AllanGP]

Hi,

Simulation mode with no aids except auto clutch here!

And a Happy Hogmanay to you all from a frosty Scotland!

Allan