What offset would I need to run 275/40?
 

Sorry, forgot to ask, but the tires I want are ina 275/40...what offset would I need to run these on a 17"? Would they rub?

Re: What offset would I need to run 275/40?
 

What kind of car?

275? Thats an odd size. 35 series would be better on an FD 265 40 or 285 35 is better.

Really depends on the rim...but I would say something in the mid 40's..
I was running 275x40x17 with OZ monte carlos with a offset of 45..no issues what so ever

It's an FD. 17x9.5" rims.

What exactly is the offset? what does a higher number mean?

Check out http://www.tirerack.com/wheels/tech/wheeltech.htm . They'll give you a great explanation.

I tried to run 275-40-17 A032R's on my SSR Comps 17x9.5 +42

The tire was real close to the rear fender lip. It looked like it would hit unless I rolled the fenders or increased the camber to at least -2 deg or mabey even both. I went with 255's instead.

I am looking into how I can get 275's to work by the time I am ready for new tires. It seems like it would be better to have +45 or higher offset to run 275's. I know people are running 275's with 9.5 +40 & +42 so mabey I only had a problem because the A032R's run wider than some other tires.

If any one else is running 275's with 9.5 +42 or less, without rolled fenders please let me know what camber settings are bieng used and which model of tire you have.

Previous set of wheels, 275/35/18 Kumho Ecsta Supra on 18X9.5 +43, rear - camber within factory specs (sorry, forgot exact). No fender rolling, no rubbing.

Also, offset and wheel width must be taken into account at the same time. An 18X8.5 +40 and a 18X10 +40 will sit very different within a wheel well.

New set of wheels (arriving next couple days, YEA!), 285/30/18 Pirelli P Zeros (regular), rear on 18X10 +44.

I'll let you know how it fits...;)

Lunar,
Are you running 255 on 17x9.5" up front too? Any problems with rubbing? An ideal setup would be 255/40/17 all around, because it maintains the stock rolling diameter and width balance. Anyone else able to get this to work w/o rubbing on a stock suspension?

Nathan;

I have 235-40-17 on 17x8.5 +42 up front.
I apreciate the smaller diameter up front because I am experiencing very very slight rubbing in the top center of the wheel wells. This very slight rubbing only occours during very high G brake turning on the track or autocross. Raising my coilovers and stifening my shocks cured about 98% of the rubbing. I imagine an upgraded swaybar might help to reduce it further.

I agree that 255's all around would be nice, since taller 275's on the rear can hurt aceleration (from a roll). As for the stock rolling diameter and width balance 235-45-17 and 255-40-17 are now the stock sizes on 99+ RS models. :)

I have pretty much what the rest is running. 325/40/17 up front(43) and 275/40/17 (38). Im not sure about the offset(front or rear. which is which) but I have absolutely no rubbing whatsoever! H&R springs lowered the car about 1.75". on factory settings... may get an alignment in spring though

thats 235 for front sorry.

I have 275/40/17 Blitz wheels for my 7. They are the rears, though. (17x9) The fronts I run 17x8's. If you go any wider than 9 in the front, they may rub unless you go with a really low profile.