DerekStangGT said:
under hard driving, even after all my suspension mods, i still get a small amount of bady roll. just enough to make my rear tires scrape the fender well when i drive hard and hit a bump. this can't go on. what should i do to stiffen up the rear? coilovers or illuminas? which would give me the stiffer, harsher ride? also, would it be bad to run the same tokico struts but have coilovers in the rear?
I would guess that the simple answer is you have fitter to big wheels/tyres on a lowered car.
So the fact that it rubs should be expected. Like trying to fit 1 pint of water into a 1/2 pint class - some of the water will spill out! EASY ISN'T IT.
Regardless of the other posts, of coruse shock/springs have an affect on body roll. And as for anti-roll bars, well they are considered by some engineers as a design flaw with the rest of the setup. In an ideal would anti-roll bars should not be required. I beleive the Noble M12 doesn't use any at all and has been rated as one of the best handling road cars in the world and will pull over 1.2g (lateral) on a skid pad.
Where are the wheels rubbing? If its the inner arch then a wider offset wheel or wheel spacer may help, but this may cuase it to rub on the outer arch, so that will need rolling out.
As for body roll, well you need some. If you don't waqnt any remove the shocks and replace them scaffolding poles, your car will handle like crap but at least it won't roll.
To get the best from the car it needs wheel travel to allow the suspension to work, it may just be a case of the suspension crashing out, in which case modified bump stops may help.
Other areas to look at could be lateral axel location, a live axel as on the GT will move sideways under extream loads, ways to prevent these are by chaning the rear link setup and adding a Watts linkage or a Panhard rod. Evolution Motorsport do a very nice Tri-link setup with a Watts linkage, that is what I would go for.
However the best thing really to do would be to revise your whole setup, remember moderation is the key, if you go to extreme with anyone thing it will be detremental to something else.
The GT was never even considered to have giant wheels and slammed suspension, hence it doesn't really work very well without major modifications to the whole suspension design and concept. With modern cars like Ferrari's and Jaguar's its a different story as they are designed for very large wheels and can cope with them, often running 19" or 20" rims.