ak47m203

It is tire specific, when I decided to go 255/40/18 I did 2 references that it is ok and not just the forum. Discountire and Falken itself.


http://www.falkentire.com/Tires/Azenis-RT-615K-14 click sizes and specs and look for the approved rims...8.5 to 10.

http://www.discounttire.com/dtcs/tir...T%7Cpc%7C75074 In discount tire it is plus zero categories

Iowa999

iTrader: (1)

OK. I'll bite.

The question isn't whether it's "OK" or will fit or whether some website says the tire is within the range of sizes for the wheel (or v.v.). The question is whether you gain or lose lateral grip. The internet is big place, so maybe there's a back-to-back, skid-pad-type comparison out there, but I doubt it. More likely, if this is going to be answered definitively for some tire, someone in an ST class will have the data that you need, so maybe you should be poking around on SCCAForums, for example.

FLK

The evox tuned by ralliart track car runs 255/40R18 ad08's. you can youtube its best motoring tsukuba battles.

ak47m203

...and I also asked you FLK about that tire size long time ago.

Iowa999

iTrader: (1)

And it's on 8.5"-wide wheels? <- the point of this thread

FLK

No I think it's on 9.5's. I run 255/40R18s though on stockers without a problem.

Iowa999

iTrader: (1)

I cannot criticize anyone (for at least a few days) for going slightly OT. I wasted several posts going on about 18" BBS wheels from a 2008+ STi in a thread about 2007 wheels. With that said, unless the tire has really stiff sidewalls, a 255/40 could well end up with less lateral grip than a 245/40 on an 8.5"-wide wheel. Add in the lower torque and I question whether this is the best option.

ak47m203

unless there will be a bck to back test, same car, same driver, same time and place. wait....just a new wheels maybe with 265 or 275.

turbodsm15

i know that the optimal grip for an 8.5" wide wheel is a tire size of 245.

Iowa999

iTrader: (1)

Interesting. I know that the optimal width for an 8.5"-wide wheel depends on which tire. Weird.

ak47m203

I dont think 255 will give you something better but spend more money and more weight on that tires. But one thing is for sure, it will fit ok. I'm still on stock BBS, I will go back to 245. Maybe one reason the FQ400 is still 245.

Bigstakk

hmmm...I was debating on throwing on some 255/40s on my MR BBS's with the assumption that there could be some performance gains in addition to flushing out the wheels some...might have to double think this one...