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      10-17-2010, 04:05 PM   #1
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Lowest Offset on 9.5" Rear on Non-M Coupe?

Just like the title says, what's the lowest offset I can get away with on a 9.5" rim on the rear of my non-m Coupe? Stock sports suspension and don't want to roll the fenders.

I think I've seen non-M roadster owners report saying they were able to get the stock M wheels to fit, but wasn't sure if they still encountered rubbing on bumps. I believe stock M offset rear is 27?

And assuming I'm keeping to stock height, wheel diameter (18" vs 19") should not matter as long as I choose the correct profile tire?
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      10-18-2010, 12:52 PM   #2
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i'm sure others would agree...

for rear offsets on a non-M...
with stock sport suspension
w/out adding negative camber
w/out letting the tire stick out past the fender
w/out body modification

9.5" width = et42
9.0" width = et35
8.5" width = et29

basically, any offset that pushes the outer edge of the wheel a maximum of 21mm past stock (8.5 x et50).
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Last edited by v3.0si; 10-18-2010 at 01:29 PM.. Reason: clarification on dimension.
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      10-18-2010, 05:55 PM   #3
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thanks, very helpful...
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      10-18-2010, 06:16 PM   #4
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I believe the lowest offset you can run on a 9.5" wheel is a 32 offset. I was able to run a 19X10 wheel with a 35 offset with 265/35/19 tire without any rubbing on a eibach/koni set up. Stock M wheels do have a low offset, however they're not that wide of a rim.
Are you planning on another set of wheels?
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      10-18-2010, 06:39 PM   #5
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Quote:
Originally Posted by misterawa View Post
I believe the lowest offset you can run on a 9.5" wheel is a 32 offset. I was able to run a 19X10 wheel with a 35 offset with 265/35/19 tire without any rubbing on a eibach/koni set up. Stock M wheels do have a low offset, however they're not that wide of a rim.
Are you planning on another set of wheels?
out of curiosity, and it could be my "newb" factor ... when a car is lowered, does it increase the amount of negative camber? i ask this because i saw on your website that your car has un unbelieveable amount of camber in the rear. (by the way, your car is absolutely stunning!) but i'm not sure the OP is looking to do that. :
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      10-19-2010, 10:12 AM   #6
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Quote:
Originally Posted by v3.0si View Post
out of curiosity, and it could be my "newb" factor ... when a car is lowered, does it increase the amount of negative camber? i ask this because i saw on your website that your car has un unbelieveable amount of camber in the rear. (by the way, your car is absolutely stunning!) but i'm not sure the OP is looking to do that. :
Yes, lowering your car will increase the negative camber. The amount of camber varies and for some reason the amount of negative camber I had resulted me having to buy new tires every 12-14 months
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      10-19-2010, 10:37 AM   #7
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Quote:
Originally Posted by misterawa View Post
I believe the lowest offset you can run on a 9.5" wheel is a 32 offset. I was able to run a 19X10 wheel with a 35 offset with 265/35/19 tire without any rubbing on a eibach/koni set up. Stock M wheels do have a low offset, however they're not that wide of a rim.
Are you planning on another set of wheels?
just toying with idea of either a 2nd set or new one all together...
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      10-19-2010, 12:20 PM   #8
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Quote:
Originally Posted by Dubbedown View Post
just toying with idea of either a 2nd set or new one all together...
LOL, in the back of mind, me too...once I get rid of my 2nd set.
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      10-19-2010, 12:46 PM   #9
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Quote:
Originally Posted by v3.0si View Post
i'm sure others would agree...

for rear offsets on a non-M...
with stock sport suspension
w/out adding negative camber
w/out letting the tire stick out past the fender
w/out body modification

9.5" width = et42
9.0" width = et35
8.5" width = et29

basically, any offset that pushes the outer edge of the wheel a maximum of 21mm past stock (8.5 x et50).
btw - would you happen to know how much space I have to work with for the fronts, using the same 3 widths as above? wonder if i can get away with a 18x9 et35 on the front...
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      10-19-2010, 01:31 PM   #10
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Quote:
Originally Posted by Dubbedown View Post
btw - would you happen to know how much space I have to work with for the fronts, using the same 3 widths as above? wonder if i can get away with a 18x9 et35 on the front...
9 x et35 is a gain of 25mm on the outside edge of the rim over the stock 8 x et47. that would absolutely be past flush unless you plan on putting in some serious negative camber up there.

i'm measuring flush at front to be...

9.0" width = et42 (may have suspension clearance issues
8.5" width = et35
8.0" width = et29

also... i've read on this forum, several posters are having clearance issues with the 8.5" x et35 using 235 tread width. since all of the above measurements use a gain of 18mm over stock, all of these may have the same rubbing issues. my personal plan is a set of front at 8.0" x et35 and a rear of 9.0" x et35. this way i'll be able to go the stock ///M tires.
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      10-19-2010, 01:47 PM   #11
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Quote:
Originally Posted by v3.0si View Post
9 x et35 is a gain of 25mm on the outside edge of the rim over the stock 8 x et47. that would absolutely be past flush unless you plan on putting in some serious negative camber up there.

i'm measuring flush at front to be...

9.0" width = et42 (may have suspension clearance issues
8.5" width = et35
8.0" width = et29

also... i've read on this forum, several posters are having clearance issues with the 8.5" x et35 using 235 tread width. since all of the above measurements use a gain of 18mm over stock, all of these may have the same rubbing issues. my personal plan is a set of front at 8.0" x et35 and a rear of 9.0" x et35. this way i'll be able to go the stock ///M tires.
I used to have SSR Comp H on the front which were 8.5 and I believe that was 35 offset as well but I ran a 225, thought the 235 would be too tall. Thanks again for the numbers.
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