biggest tire without notching/rolling?

[Tom Tom Turbo]

I'm trying to figure out what the biggest wheel/tire combo I can stuff in the rear without notching frame rails or rolling fender lips. I have 17x8 wheels with 4" BS on a 245/45/17 right now, but I am talking only at the drag strip. The slicks I have now are 26x9.5x15 on 15x8 4" BS draglites. How big can I go? The car has new Kirban heavy duty rear springs and air bags, ATR sway bar, UMI LCAs and Moser 30 spline axles.

Thanks!!!!

 

[WE4 WARRIOR]

question

i'msorry i don't have an answer for you. but i have questions. hope you do not mind. how does the buick ride with 17s. do you have room to go any larger tires on those rims. thinking about going with 17 inch torque thrust. thank you.

 

[Tom Tom Turbo]

I can't honestly tell you how changing just the wheels will affect the ride. I did Bilsteins, progressive springs, air bags, and LCA's all at the same time and then added the wheels. It rides firm but much more responsive. There is no more room for tire in the back, I am about 1/4" from the side of the tire rubbing frame rails. Up front, the tire has smoothed out a part of the fender liner, but now it doesn't rub anymore