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      05-12-2020, 01:47 PM   #1
P3PPY
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NASCAR style wheels for E85 non-M

I'm toying with the idea of some NASCAR-style, black, steelie, deep rims for the car. In so doing, I'd buck the trend of getting a much bigger wheel and would go with 16" if I could, although there are many more options if I were to get 15" to fit over the brakes.
Clearly with the OEM offset of 47, it's going to be hard to get very much "deep" at all, but it looks like offset isn't a hard and fast rule.
While some are quite heavy (40 lbs) there are a couple DOT-approved mfgs that actually come in under my current 23ish lbs.

Ideally I would put the widest tires possible front and rear. I don't want different camber than stock. I'm at stock height and likely to remain so (unless it looks REALLY funny) and I don't want to roll fenders, cut liners, etc.

I have a couple questions then:
1. Regarding physics of the car and the offset, is it okay to deviate the offset from OEM very much?
I drive spiritedly on the track on rare occasion, and I want to maintain the stock feel (or improve it) -- but definitely not any worse.

2. I understand that my overall height needs to be within 25" diameter up front and 245 width or less to keep from rubbing. On a 16" wheel that would could theoretically allow for 245/45/16. However, (and this hinges on the offset/handling question above) if I were to push the offset back some, I suppose that would turn into a 225/50/15 -- any narrower and it would be funny. In order to get that bulged sidewall look would I need to be more narrow than the stock 8" width, up front at least?

3. In the rear there's obviously more room to play with, but 245/45/16 gets me pretty close to the current width yet may allow for some play with the offset in order to achieve the right deep look. Any thoughts on that?

4. With non-matching wheel/tire diameter sizes, will this mess with my TPMS or traction control?

I want the back wheels to be spot-on. If the front are a tad too narrow or not deep enough looking, maybe that would still be okay, as long as the back wheels are getting it done.

Thanks!
And here are some pictures of what I'm thinking of



Whereas this looks super lame, so I definitely want to avoid this:


Likewise, these are too shallow to look good:
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      05-12-2020, 04:39 PM   #2
3002 tii
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I’d go for 17” just in case you ever decide to upgrade your brakes. I think 3.0si brakes are bolt-on (and inexpensive) but would require 17’s at min.

Too low of an offset and you risk putting stress on the hubs. But if you’re not willing to add camber I don’t think you’ll even have the option to go that low so seems like a non-issue in your case.

Non-matching front to back won’t matter since you’re not AWD.
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      05-13-2020, 09:59 AM   #3
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I assume then that there's a calculator for figuring out my widest tire if I can't go with very low offset? And what exactly would be "too low" of offset?
Otherwise, what's the widest tire I can go in the rear with completely stock setup? All I've seen seems to involve camber changes
Thanks!
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      05-13-2020, 11:21 AM   #4
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Quote:
Originally Posted by P3PPY View Post
I assume then that there's a calculator for figuring out my widest tire if I can't go with very low offset? And what exactly would be "too low" of offset?
Otherwise, what's the widest tire I can go in the rear with completely stock setup? All I've seen seems to involve camber changes
Thanks!
How much tire you can stuff is function of rim offset and width. And secondarily how much camber you have and what kind of tire you’re tinning (some run “wide” or have more square shoulders).

You need to some research, no one answer will fit because it depends on so many variables.
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      05-14-2020, 08:17 AM   #5
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So with stock setup, do you (or anyone else) know what is the "safe" void up inside the wheel well? Is it like 285mm from side to side, for example? And at what point in that void is the face of our hubs? From there I can play with sizing and offset till the cows come home
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