as to suspension, we were moderately stiff, with 52 % weight to the Rear. I thought about using a four link set up to get a better weight transfer, but that just works for the hole shot, and not what you want at speed. I had two problems last year, I could not get on the wood, untill I was long in second gear due to wheel spin, and once I hit 215 I was at the aerodynamic limit of the body and was getting several inch's of lift in the front, even with a lot of weight on the front. The Factory lift numbers for my vette are 440# of lift at 200 mph, so you can see how much this changes on a production car with just a small increase in speed.
What I can say is the car ran straight and true, like it was on rails untill I took some weight out of the car then the tires broke loose at top speed, I had to pull the chute to prevent a spin.
I have not tried the wide tires, but in 1990 when the zr1 came out it was run at bonneville, bone stock. According to the team, I was told it was horribly unstable at 180. Once again production body.
I believe, you will find once you vist Meca ( the flats) and see how, loose the first 1/8" is and how hard the surface is underneath, you will come to the concusion with the majority, that what you want is a small foot print with a lot of weight. But Hey go for it and good luck.