Bill_VA
04-30-2011, 09:40 PM
I went and got better tires for my Cobra. I had 11,000 miles on my Sumitomos which held up pretty well. However, doing so was not a simple matter of mounting new tires and enjoying the driving. Here was my situation, with my Sumitomo 315/35/17 tires the tire-to-fender clearance was at a premium, sometime they would rub. Now the bad news, the Sumitomos are 11 15/16" wide while mounted on my 10.5" rims. The Kuhmo Ecsta XS 315/35/17s are 12 3/8" wide, 7/16 wider on the same rims. Note that the shoulder profile on the Kuhmos are less rounded as compared to the Sumitomos, which required a bit more room for clearance. For me, this was a deal breaker. My solution was to change from my SN95 rear axles to the shorter Fox axles, they are 3/4" shorter, use adapter brake caliper brackets from Forte. While torn down I also replaced the bearings and seals. Since I went 3/4" narrower but still wanted the tires as far out as possible, I made up some of the difference with billet aluminum wheels spacers found on eBay (real nice and only $40). Since I used spacers I had to have a bit longer lug studs too, had a machine shop cut down 3" studs to 2". All this gave me an additional 1/4" of tire-to-fender clearance that I always wished I had.
I'm not a racecar driver by trade, but these tires definitely feel much grippier. I'm betting that after a couple more heat cycles and a few hundred more miles, they will feel even better. You know, I think that having the less grippy Sumitomos for the first set of tires may have been good for me to learn how to drive a car like this.
I'm not a racecar driver by trade, but these tires definitely feel much grippier. I'm betting that after a couple more heat cycles and a few hundred more miles, they will feel even better. You know, I think that having the less grippy Sumitomos for the first set of tires may have been good for me to learn how to drive a car like this.