1. increase steering lock (default is 15 degrees at the car wheels);
2. add caster and camber, LOTS of it;
3. put brake balance forward to ~75%;
4 do not set the suspension too low and/or too hard;
5. warm up tyres properly.
I drove a 914/4 a few times, a 914/6 too. I own a Fiat X1/9 (with Lancia engine).
The Fiat is a bit more 'terror' than the 914. Bit more weight in the rear (42/58).
Yes you can go very fast through a corner but when it lets go, start praying!
The 914 is the same, check the speedo.
In a sim it is very easy to forget how fast you are going.
Even if it can take corners faster than any other car,
2x 50 km/h would be impossible... still they're good.