I don't think a 12mm offset will work. You can go between 25-35, preferably 30mm.

 

An additional 5%. With a 265/35/18 when your speedo reads 60 you would actually be traveling 56.9mph.

Check it here- http://www.miata.net/garage/tirecalc.html

 

+12mm is ok on a 9.5" wide wheel.

 

Pretty cool. But what are you using for stock tire size? I guess the touring Z w/18" rims has the same wheels/tires all around, right, but I forget what the specs were?

I feel like you guys are leaning more towards 40 sidewall, though. Why the higher sidewall? Is it better for performance or something? I thought I read just recently somewhere that it might not be as good for cornering bc there's more space for the rim to move around, or something along those lines? I'm not really sure if I read that correctly, though.

 

I was comparing vs the stock 245/45/18 size on the Track model. The 275/40/18 is the same height- 26.7" tall. That's what you need to look at. Of course that is just for the rear tires. The fronts are 25.7" tall. A 275/35/18 is 25.6" tall and would be perfect if you wanted 275's all around. Try to keep the diameter of the tires close to original spec.

It's true that a tire with smaller sidewall will be a little more responsive but that's not to say it will perform any better on track. Unless you are a racer and drive for a living I doubt you'll notice much.

 

I have 18 x 9.5" on all four wheels, with a +30 offset all around. I have a 25mm spacer in the rear and i'm installing a 10mm spacer in the front. Everything fits nice and dandy.

Heres a great link to compare tire sizes and the dimensions of each tire.
http://www.miata.net/garage/tirecalc.html

 

Thanks for all the input. I think I'm going to stay with the 18x9.5, +12 offset wheels, all around, and wrapped in 275/35/18 tires. I just hope everything fits to stock and w/o any issues or modding/upgrades necessary. I just need a good price on them now! I'm looking at the Work Emotion CR Kai's.

 

Let us know how it goes!

 

BTW, for any that may have been wondering, I've decided to hold on to the car. I just don't see it worth selling, and my love/respect for the Z has been rejuvenated!

 

Here's a pic of the Works 18x9.5, +12 all around on some member's ride.. still trying to decide what finish, though:

 

Wow that car looks really good with the works.

 

Won't a +20 give it more of a "concaved" look? Thanks.

 

I was under the impression that lower offsets meant more concave, so +12 would be more concave than +20.

 

Correct.

 

here's my setup:
- 18x9.5 all-around
- +22 offset all-around
- tire size (f)245/40, (r)265/35
https://my350z.com/forum/showthread....ighlight=advan

 

I just posted this pretty cool tool in a new thread:
http://www.wheelsmaster.com/rt_specs.jsp

It looks like my new wheel set-up of 18x9.5, +12 all around with 275/35/18s will be 2.7" wider in the fronts, 2.3" wider in rear (as compared to stock 17s). Both front and back tires will be 0.7" lower in ride height. Don't forget to take into account the offsets!

 

Never mind. I think I was using that tool wrong. Anyways...I've decided to still go with the 18x9.5, +12 set-up all around but with 265/40/18 tires on all four wheels instead. Either this, or a staggered tire set-up, but I'd like to be able to rotate the wheels/tires more than anything else. Taking into account Nihilation's comments and some other suggestions, this should keep me at stock height and potentially avoid any problems I might encounter w/TCS, or whatever, whatever. Still a little concerned about this set-up front on the Z, but I think it's much better than my previous choice (275/35/18) + personally, I would reserve the 275s and up tires for 10" wide+ wheels.

 

Takteh- 275/40/18 is actually what Nissan recommends as far as tire sizing goes for the 9.5" rear wheels. It is pretty much straight flush with the lip of the wheel and is definitely the best fit and as wide as I'd run on that wheel. The 265/40 as I'm sure you know is .3" less diameter which is a good compromise if you can't run the 275/40. Only issue I see is that the 265/40 is still taller than oe in the front which would make the front end of your car ride a tad taller and squat the rear some. This will also change the weight distribution although you'd probably never notice it.

Personally I'd run a 275/35 front and a 275/40 rear if I could find a good tire offering both sizes.

So which tires are you going with?

 

Nismo 18x9.5 (+30) all the way around on 275s (35 front/40 back)
Kuhmo ECSTA SPT, with the current wear, they may make it to 20k miles, work excellent in the rain.
Pics are before the drop with Tein s-tech springs.
More pictures here http://www.hypersprite.com/auto/pict...17/default.asp



My next set of tires may be 275/35F and 285/40R on BFG KDW (NT) unless they come out with a 275/40 before that time.

Chris

 

Not sure, but I'm thinking I might have to give up this same tire size all around thing just bc I don't want to compromise anything on the car and how it was meant to handle/drive. So then, if I have to choose a staggered tire set-up, I am thinking:

(1) 265/40/18 Front, 275/40/18 Rear like you said (Same HT diff vs. stock),
(2) 255/40/18 Front, 265/40/18 Rear (Same HT diff vs. stock), OR
(3) 255/40/18 Front, 275/40/18 Rear (2xSame HT diff vs. stock)

More than anything, I'm hesitant about 265 fitment up front and don't want to have to roll fenders right now.

Also, if I'm going staggered tire, maybe I should just consider 18x9.5, +20 Front Wheels/18x9.5, +12 Rears instead of 18x9.5, +12 all around? (to give me that 8mm extra width clearance). But I don't know if that'll look as "bad-***" as the concave +12s all around.

I would just get 18x8.5 fronts, but I'm thinking (A) about resale value and how only a few might opt to pay good money for 8.5 up front, (B) I think I'd just rather have 9.5s up front for looks, but not if it can't be done, and (C) if WORK ever releases a 10.5 for the Rear, I could just move my 9.5s up front, get rid of a pair, and really have some nice wide/stagger.

Man, I'm killing myself trying to make a "perfect" decision!