Need to fix body roll
Tech Contributor
Joined: Oct 1999
Posts: 41,058
Likes: 9,820
From: Charlotte, NC (formerly Endicott, NY)
You might need to raise the rear of the car to prevent that roll over damage. With those tires you are almost an inch lower in the rear than the stock car is. 26.5 stock diameter rear tire Vs 24.8 with your spec tire. Also with the 285 in the front Vs the stock 245 you are changing the balance of the car considerably. As you suspect you should probably increase the diameter of your front sway bar which will help reduce body roll and induce some understeer in the front to compensate for the larger tire width. Maybe look at the GM C7 T1 suspension kit. You get stiffer sways, new non adjustable shocks and new control arms that probably have stiffer rubber bushings so you have less deflection.
Bill
Bill
Thread Starter
Cruising
Joined: Oct 2017
Posts: 13
Likes: 2
I had those wheels before. They're 14mm more inside than my 18x10.5 ET51 forged wheels, and that makes a huge difference. Combined with significant lack of sway bar support and increased lean, they must have caused this damage.
FYI, I was able to use those wheels with no damage using 750#/700# coilovers and aftermarket sway bars. Here's the video of my best lap with these wheels and 305/660/18F, 315/680/18R Pirelli DH scrubs:
https://youtu.be/tjSg7PRvaHw
I don't see anything against using stiffer sway bars and single adjustable coilovers in the rules.
FYI, I was able to use those wheels with no damage using 750#/700# coilovers and aftermarket sway bars. Here's the video of my best lap with these wheels and 305/660/18F, 315/680/18R Pirelli DH scrubs:
https://youtu.be/tjSg7PRvaHw
I don't see anything against using stiffer sway bars and single adjustable coilovers in the rules.
Thread Starter
Cruising
Joined: Oct 2017
Posts: 13
Likes: 2
You might need to raise the rear of the car to prevent that roll over damage. With those tires you are almost an inch lower in the rear than the stock car is. 26.5 stock diameter rear tire Vs 24.8 with your spec tire. Also with the 285 in the front Vs the stock 245 you are changing the balance of the car considerably. As you suspect you should probably increase the diameter of your front sway bar which will help reduce body roll and induce some understeer in the front to compensate for the larger tire width. Maybe look at the GM C7 T1 suspension kit. You get stiffer sways, new non adjustable shocks and new control arms that probably have stiffer rubber bushings so you have less deflection.
Bill
Bill
i am looking into sway bars. my hope is to be able to find a front swaybar with the best rate to fix the balance issue with the stock rear one installed as well.
Racer
Joined: Jul 2018
Posts: 306
Likes: 15
