18" tire selection

[MPbdy]

Seriously considering ordering new wheels.  Going to run staggered for the first time ever.  Always have had square 255/40/17 or square 285/30/18.

New front wheel options won't allow the 285/30/18, and I don't have room to run the 295/30/18 in the rear.

Wheels are 9" front and 10" rear.

Options -

A) Run 255/35/18 square - This is actually a smaller tire in the 18" size than 17".  This is probably the least attractive option as I am looking for a performance benefit.  I will be making more power in the future.

B) Run 255/35/18 front 265/35/18 rear...less of a height mismatch.  A little extra tread for the back.  A little bit taller than stock in the back but not a huge amount.  This seems to be a fairly common setup.

C) Run 255/35/18 front 275/35/18 rear...huge rear tire.  Longer gear ratios.  May look stupid?  Appropriate rake direction, taller rear vs front.  This is attractive cost/performance wise since the 275/35 is the same price as the 255...but I'm just worried about that rear tire being humongous.  Also ride height is a concern...

D) Run 255/35/18 front 285/30/18 rear...maximize fitment and traction.  Shorter gear ratios...don't actually hate this.  Shorter rear tire than the front by .3".  Reverse rake.  Will this look dumb?

265 wide is an extra $50 per tire.
285 wide is an extra $100 per tire.

size                  height      section                   tread width
255/40ZR17   25.1"   10.4"   6/32"   9.9"   8.5-10"   SL   1477 lbs   51 psi   26 lbs   827
255/35ZR18   25.1"   10.2"   6/32"   9.5"   8.5-10"   RF   1477 lbs   50 psi   25 lbs   828
265/35ZR18   25.4"   10.8"   6/32"   10"   9-10.5"   XL   1609 lbs   50 psi   27 lbs   817
275/35ZR18   25.7"   11"           6/32"   10.4"   9-11"   XL   1709 lbs   50 psi   27 lbs   809
285/30ZR18   24.8"   11.3"   6/32"   10.8"   9.5-10.5"   XL   1609 lbs   51 psi   27 lbs   836

[largeorangefont]

Without 8.8 conversion.. C

With 8.8 conversion D. This wont look bad, you wont be able to tell the tire is shorter.

[MPbdy]

You're referring to the gearing when talking about the 8.8?

I'm afraid it'll look like a monster truck with the 275's.

[ZDan]

You're referring to the gearing when talking about the 8.8?

I'm afraid it'll look like a monster truck with the 275's.

FWIW here's my car on 245/40-17 fronts and 275/35-18 rears:


I don't think 25.7" tires look big at the back of the car, personally.

[largeorangefont]

You're referring to the gearing when talking about the 8.8?

I'm afraid it'll look like a monster truck with the 275's.

Yes, I was thinking of gearing.  275/35/18s will look great. Car will look lower, and actually be slightly higher off the ground.

[Mik3ymomo]

My first FD I ran 255/35/18 front and 285/30/18 rear.
Here is a photo. It's on H&R springs and Bistein HD's


Next was my second FD that ran 235/40/18 front and 275/35/18 rear
Stance Coilovers



My third FD running 235/40/18 front and 265/35/18 rear
Tein Coilovers

[MPbdy]

Awesome not to find a hookup on wheels :x

[paul_3rdgen]

I ran option C for many years and I thought it worked and looked great

[Mik3ymomo]

Depending on your offsets the 255/35/18 in the front and your ride height it will probably require a fender roll. Also the 255/35/18 in front would rub my fender liner on occasion. Something to becareful of on the passenger side as the wiring harness runs under the front part of that fender liner if you are still running the FD front harness there.

The rear can fit a huge tire. I've seen people running 305+mm back there with coilovers, aftermarket trailing arms, toe links and lower control arms and a properly thought out offset wheel.

You will find that 275/35/18 size has a slew of tire choices and the prices of them are considerably more affordable than the 285/30/18.
I would even consider what Paul used with the 295/30/18 if you wanted a wider tire back there. I think 285/35/18 would be ok but not my first choice for a rear tire. Not unless it's a drag radial that didn't come in a 275/35.
Drag radials don't come in ideal sizes for an 18" wheel in Ideal FD sizes.
The BFG was the only one I ever saw.

[MPbdy]

Thanks Mike.  I'm pretty happy with the feedback everyone gave on the 275/35/18.  I thought it would just be way too huge for the car.  I'll be running R888's front and rear.  Love that tire.

I ran 18x10+50 for a while with 285/30/18 tires.  The front I have a roll and the rear I have a trimmed lip with a 12mm spacer.

18x9+35 front with a 255/35/18 is the same tire height as I run with 255/40/17.  It will stick out a couple MM more than the 18x10, but it's a narrower tire by a lot.  I don't foresee an issue.  Sometimes I would rub the inner fender, but not since I put Ohlins on the car. 

18x10+35 rear with a 275/35/18...lot taller tire.  Pushed out just a hair more than the 18x10 wheel was, but with the slightly narrower tire I don't foresee any issues here either.   

[skeeg]

in reference with rear gearing and tire options, having the stock 4.10 rear with a standard t56 what height (overall) is best? in regards to HPDE type racing, local track for me is lime rock in CT.

ive been debating the 295 front and rear with 18x11 +45 stock body with roll, or running cheaper rims and going with 265.

[paul_3rdgen]

With taller tires the 4.10 gear isn't too bad, I actually like them.   With 25" stock height, the 4.10's make first gear pretty useless.

[skeeg]

i dont have the ability to switch out for the 8.8, so maybe running r888 in a 305/35/18 would actually help out being a 26' tall tire.

[Exidous]

I would still consider a 295/30-18. Tires are not created equal in section width. A 315 wide falken 615 is 1 full inch narrower than a Michelin PS2 315 wide tire.

All 295/30-18 will have the same diameter (25") but overall width can vary greatly. 255/35-18 in the front of course.

I have two sets of wheels. One runs 285 all round and I would not do it again. Next set will be 255 front 295 rear. My other set is my "basher" set 255/40-17. I like how the 255's drive steering wise MUCH better.

[gnx7]

I ran option C on the street on my original 3:90 gear'd FD and 440rwhp.  18x9 front and 18x10 rear Gram Light 57 Pros.  Loved those wheels.

For the track I swapped over to 18x10.5 CCW's on 285/30/18's.  These tires drove like crap on the street and would tramline on every crack/groove and required 2 hands to drive (aggressive alignment).  I would swap back to option C and the car would drive like a kitten again... just turn in was slower on the same alignment.