Hey guys,
I've decided on 18x8.5 and 9.5 track wheels (probably te37's or ce28n's). Now I'm debating on going with 255/35 and 275/35 or 245 or 255/40 and 275/40. I'll probably get some street tires instead of R compounds. I think I need a little more experience before going with the R compounds.

Any advice on which profile would be preferable and why would be greatly appreciated.

 

I believe the taller tire should theoretically increase your gearing, so say if 2nd went to 60 on a 35 series tire, then it may go to 63 on a 40. Obviously those numbers are strictly pulled from midair, but should sorta show you what effect it would have.

You could probably go wider on the tires if you want, I fit a 275 on a 7.5" rim with no problems.

The wider the tire, the taller the sidewall will be, the sidewall on a 275/40 will be taller than a 255/40, as I believe the 40 is some sort of percentage of the width of a tire.

 

thanks for the reply christoc. my question was actually directed more to the aspect ratio. I'm wondering if a 35 series tire's sidewall is too stiff to be effective when compared to a 40 series tire as I'm sure some amount of flexing would be wanted.

 

I would go with a 35 series tire because I would think it is harder to roll on its edge because its shorter. Also, to add to Christoc's reply the smaller diameter tires help you accelerate faster but take away your top speed per gear.

 

I went with 40s because of the tire geometry and over all footprint. The new Pirelli tires, for instance, have too much of a rolled edge at 35 and the sidewalls show too many stress cracks early on.

$.02