Originally Posted by Kev
Interested in getting a set of tires for summer to fit on a set of 19X9.5, 19X10.5 rims. I was looking at 265/35R19 and 305/30R19 tires. All 3 options that I liked, Conti CSC3, Michelin PS2, and the new Bridgestone Potenza RE-011 all came in a mixed standard load and extra load. No single brand offers both front and back tires in XL. What would be the ramifications of mixing SL and XL tires of the same brand?
I believe the XL rating on the 19's is to handle the heat buildup in the smaller tire carcass at high speed. 18's don't need it because they have more internal volume and they don't get as hot.
My on the road experience is that non-XL tires tend to feel a bit wobbly at full throttle over about 7000RPM. The sidewalls seem to have trouble with the higher horsepower. However, I wouldn't worry about it - I've run the same non-XL tires on the track and there's no problems with them.