315 BFG + 17x10.5" + Cobra IRS..install details w/ pics

[wjfawb0]

SEE END OF THREAD FOR RESOLUTION


Hey all. Here is the history of my wheel tire combo.

Started off stock 17x9 with 275/40-17 F1s all around.



Wore out the stock rear tires in about 4 months(12,000 miles). Got 315/35-17 nittos on two 17x10.5s for the back. Also bought 1" hubcentric H&R wheel spacers to prevent the IRS bolt from touching the tire sidewall when the suspension was unloaded. Needed the spacers stock, but after grinding down the IRS bolt heads about halfway the nittos would clear the IRS bolts without the spacers.

Write up with pics here:
http://www.modularmustangs.net/showt...5870#post15870

Without 1" (25mm)spacer:


With 1" (25mm) spacer:



Nittos wore out after just 2 months(6,000 miles). I bought GS-D3 goodyears to put all around the car on the stock rims. 275/40-17 on the front and 285/40-17 on the back.



Worn out nitto on left(meaning not safe at all in any amount of rain at highway speeds):



3.5 months (11,000 miles) later the rear 285 GS-D3s are past the wear bars (2/32" tread). The tires cause the rear end to get squirrelly in a decent amount of rain at anything above 65mph. Time for new 285s for the rear.

Wore out 285 GS-D3:



While waiting for the new GS-D3s I bought some 315/35-17 BFG drag radials from tire rack for $138 each. I get them mounted on my 17x10.5 wheels and test fit them. I expected the sidewalls to touch the IRS bolt with the suspension unloaded (BFG 315 much wider than nitto 315), but I didn't expect the sidewall and IRS braket to both touch the sidewall with the suspension unloaded and loaded(car sitting on the ground).


Left = BFG 315 on 10.5", Right = 285 GS-D3 on 9"


BFG


GS-D3


BFG touches IRS bolt and support with suspension loaded and unloaded





285 GS-D3 on 17x9" rim is no where near touching shaved IRS bolthead





BFG from side


GS-D3 from side


comparison of BFG 315 and GS-D3 285


BFG 315 vs Nitto 315 comparison


So, now I am looking to get a 1/4" to 1/2" spacer and some longer wheels studs so I can run the BFGs at the track. What has been other's experiences with the BFG 315/35-17s on 17x10.5" rims??? Did you use the 1" hubcentric spacers with integral studs, or did you get longer studs and a simple spacer??? I sold my fricken 1" spacers not expecting to have this problem(wasn't planning on the BFGs). Bummer. At least a fellow 03 cobra owner is enjoying them now.


Thanks.

-Jason