what tire diameter?

 

Stock suspension is optimal for launching, its very easy to launch on stock suspension at least I think so. But to the guy who said our suspensions are too stiff(especially most aftermarket), I agree. I get no weight trasnfer with JIC coilovers, and set on full soft. Ive been thinking about switching from JIC's to Hotchkis springs. The springs rates in the rear are actually softer than stock(slightly) and slightly stiffer in the front. You can run them with stock shocks if you want due to the slight drop. I think these along with Koni yellow's and a set of sways would handle as good as my JIC's now, with a more comfortable ride, and I could dial in more + camber with my camber arms/spc toe bolts for a larger contact patch.

As far as a 9.5" wide rim, I wouldnt do more than a 295/305 on one, it would look too pudgy for my tastes after that. Although it will be pudging some at that point.

 

yes it is for a 20" wheel. don't remember the aspect ratio, but i saw the saleen s7 has them on the rear so i knew someone had to make it. ok, just looked on the saleen sight and holy hell it actually is a 345/30/20 on a 20x12 rim. kinda weird though, they say it is a pirelli michelin pilot sport? ok now at the tire rack they have a pirelli rossa assemetrico 345/25/20 for $467 each. and found the michelin pilot sport ps2 in a 335/30/20 for $396 each. the 335 has an outside dia of 28" and section width of 13.5" and treadwear of 220. this one comes on the carrera gt. in comparison the 245/35/20 has an outside dia of 26.8" and 9.8 section width. would look menacing from the rear to see 27"'s of tire in the back, hahhaa. i heard a couple members have gotten their wheels widened for about $175 each, as you would need a 20x12 to fit this tire correctly. then do some fender mods to fit it inside the wheel well. or just a set of widebody rear flares.

 

btw, the pirelli 345/25/20 has the exact same height as the 245/35/20, at 26.8". very very tempting, lol. unfortunately pirrelli only makes a 245/40/20 at 27.7" tall in the same tread pattern.

 

If you look at everyone that is having major traction problems its because of either Suspension, camber, or tires. I believe if you address this issue by those means you will improve but not eliminate major traction loss.

When I run the Zeals on soft they are softer than any other coilover setup Ive rode in, I had my camber corrected by over a degree and Im running 285's out back now and the traction increase is very noticeable. I gained half of 2nd gear back all of 3rd and so on.

Now if I stiffen my suspension, had my camber like before and was running 275's my tires would light up in 3rd.

you have to allow for that weight to transfer.

 

Just last night I had my tire guy mount (or should I say stretch) a pair of 325/30/18's Michelin Pilot's on a set of 18x9.5" Nismo's LMGT4's. They don't rub and seem to work well.

 

Try this:

This product (Shurtrax) is a 24" x 36" x 3" bladder with a vinyl protected outer shell. When filled with water it adds 100+lbs of weight to aid in various driving conditions. Use in the trunk of an Automobile or under the rear seat of any Van or SUV.