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So Nizmo Man just answered your question. As long as the mathematical rolling circumference is identical, width DOES NOT matter. I had a guy turn blue in the face trying to tell me width of tire will affect the system. Big myth. Even the smallest difference in outer diameter circumference won't be noticeable to you or the computer but eventually will wear down the mechanical aspect of the differentials and/or transfer case. Largest problem of a staggered offset on awd is the tires. It's extremely difficult or near impossible to find a front that rolls the same as the rear. Mix matching tire manufacturers has sometimes worked but the time and research needed to find such a match is ridiculous.

ok, cool.

so theoretically if i ran a 9"f and 10"r both with say 265/35/18 tires, obviously one with a relatively straight up and down sidewall and one very slightly stretched, there would be no issue? or would the sidewalls pull the tire diameter down enough to create a difference,
not sure if there is a calculator for that?

Manufactures design the tire without stretching in the process. Tire stretching alters the tires overall dimensions which throws out every wheel calculator known. This is were a tire tape and knowing your calculus. Just how Nizmo Man stated, tire pressure will also alter rolling diameter. This is where I was stating mix matching tire manufacturers sometimes works because their specs of a 265 of a Hankook tire will be different of a 265 from Nitto. This applies across the board.

I know it's a lot to take in but your best bet is find the tire you'd like to run. I.e. BFGoodrich. Go to bfg's website and look at their specs for the tire. They'll give you a rolling outer diameter. Now the fun part is to find another tire with the same measurement. Here's another monkey wrench. Tire pressure is everything. You'd be running the recommended tire pressure at all times. So pressure up front will differ from the rear hence the two different tires. All specs given on the websites are given with the idea of the tire being properly mounted and properly inflated.

ok, cool.

so theoretically if i ran a 9"f and 10"r both with say 265/35/18 tires, obviously one with a relatively straight up and down sidewall and one very slightly stretched, there would be no issue? or would the sidewalls pull the tire diameter down enough to create a difference,

not sure if there is a calculator for that?

I reckon you would, hence the different tyre sizes for the different wheel widths.
  • Like 1
  • 3 weeks later...

Hi all, i am new to this forum and this is my first post so bear with me. I am currently looking to buy wheels for my new r32 GTR. I have found a set that have the following specs.

Front: 18 x 9 +30

Back: 18 x 10 +18

Just wondering if anyone is running similar specs? Do the front clear the calipers? No need for any guard work?

Cheers

Hi all, i am new to this forum and this is my first post so bear with me. I am currently looking to buy wheels for my new r32 GTR. I have found a set that have the following specs.

Front: 18 x 9 +30

Back: 18 x 10 +18

Just wondering if anyone is running similar specs? Do the front clear the calipers? No need for any guard work?

Cheers

Those wheels are terrible for your car.

Since you're new to the Internet, I'll help you out.

1. ATTESA does not like different rolling diameters. Stick to the same sized wheels and tyres all round. So you'd want either the front OR the rear sizes all round.

2. Brake clearance is determined by the wheel spoke design/space behind the spokes. You have provided zero information on what wheels they are besides the sizes, so your guess is as good as ours.

3. 18x9+30 is the standard R34 GT-R wheel specs, which doesn't require guard work (depending on how low you car is). 18x10+18 will require guards rolled and negative camber to fit.

Welcome to the forum and happy searching. Use Google e.g.: type this into the search (without quotes) "r32 gtr wheel fitment site:sau.com.au".

Thank you for the reply that definitely helped a lot. I didn't know about the attesa system not liking different diameters so that's great thanks. The wheels I am looking at are work GT5's, and I have changed the sizes to 18 x 9 +30 all around. Would they be more suitable??

Cheer

Awesome sounds good thank you for the advice!! The other size I'm looking at is 18 x 10 +38, but I'm unsure as to how they will sit. If anyone on here has photos of their wheel set up please post some!!

Cheers

As for the look, I want to run a clean close fitment but run as neutral camber as possible. If necessary I can roll the guards but I don't want to flare them and ruin the natural body shape.

Awesome sounds good thank you for the advice!! The other size I'm looking at is 18 x 10 +38, but I'm unsure as to how they will sit. If anyone on here has photos of their wheel set up please post some!!

Cheers

Nah, forget that spec.

As for the look, I want to run a clean close fitment but run as neutral camber as possible. If necessary I can roll the guards but I don't want to flare them and ruin the natural body shape.

Scroll up and read the last sentence on post #3328.

Thank you for the reply that definitely helped a lot. I didn't know about the attesa system not liking different diameters so that's great thanks. The wheels I am looking at are work GT5's, and I have changed the sizes to 18 x 9 +30 all around. Would they be more suitable??

Cheer

Bro you need to google image that. Seriously.

Check out r32 gtr with r33 gtr wheels. That will answer all your questions.

New wheels for my R34 GTT

Front: 18x9.5 +27

Rear: 18x9.5 +27

Enkei NT03-M flat black

I am going to run 235/40/18 in the fronts, and 265/35/18 in the rears.

Any suggestions are welcomed.

Test fitment today, love them. Currently 265/35/18 all around, but tires are trashed.

20150610_115847_zps164ee0s7.jpg

20150610_115824_zpsjxjixgip.jpg

Edited by 604JD
  • 4 weeks later...

guys- who's running 18x10 +22 or near size wheels & how much camber are you running to tuck them?
currently has 235/40 and they stick out a good 15-20mm~

got defected for them sticking out so only solution is to tuck them in as i dont want to change wheels,

last alignment i had was -1.4

i'm thinking close to -1.8-2 as i will be lowering it bit 20mm more so the top of the tyre just tucks in.

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