[Wolfman64]

Originally Posted by limeypride

Agreed. I did the math before I made the change. However, I did't consider interior-top wheel-arch rubbing (as opposed to edge-arch rubbing which is NOT a problem).

Stock tires + H&R M550 springs == no issues.

Upgraded tires as mentioned earlier == no issues rear. Initially, no detectable issues front. Eventually, I started to hear rubbing during slow, tight maneuvers. So I setup a tight turn test and listened intently. The most pronounced running was driver-side from 75% lock... possibly because it's the side I'm closer to. Physical examination doesn't reveal much. Regardless, it's severe enough for me to decide to switch them out for their lower-profile counterparts.

Just saw that you have 295's in the rear. If you go back to 275's, there is a 1.8% difference. That's minor IMO.

Have had several MB's that have 19" in front and 20" in rear. Our GTC has a 3.4% difference in circumference and that is factory...

[Wolfman64]

Originally Posted by limeypride

Agreed. I did the math before I made the change. However, I did't consider interior-top wheel-arch rubbing (as opposed to edge-arch rubbing which is NOT a problem). It's the increased tire-wall/profile that is causing the problem. This has not been an issue with my prior Ms because I've never gone for a 35% profile before.

Stock tires + H&R M550 springs == no issues.

Upgraded tires as mentioned earlier == no issues rear. Initially, no detectable issues front. Eventually, I started to hear rubbing during slow, tight maneuvers. So I setup a tight turn test and listened intently. The most pronounced rubbing was driver-side from 75% lock... possibly because it's the side I'm closer to. Physical examination doesn't reveal much. Regardless, it's severe enough for me to decide to switch them out for their lower-profile counterparts.

The only difference will be visual. The rear already looks beefier with the wider tire and the 11mm spacer. Might need to go up a bit on the front spacer...


Had some weird double-post. The website stops responding from time to time for me.

[limeypride]

Originally Posted by Wolfman64

Just saw that you have 295's in the rear. If you go back to 275's, there is a 1.8% difference. That's minor IMO.

Have had several MB's that have 19" in front and 20" in rear. Our GTC has a 3.4% difference in circumference and that is factory...

Interesting... I've been wrestling with that solution especially since it only requires I replace 2 tires. The problem I face is there's no data and nobody at BMW willing to answer, "what is the tolerance?" Given that, I'm kinda stuck because getting it wrong is something likely to break some major drivetrain components (transfer case, etc.).

Each 4WD solution seems to be different--Audi's, for example, on my RS7P had a near-zero tolerance requiring a square setup where I ran 295s all-around--that was kinda like driving a bobsled on most freeways.

Which GTC are you referring to?

[limeypride]

Originally Posted by Wolfman64

The only difference will be visual. The rear already looks beefier with the wider tire and the 11mm spacer. Might need to go up a bit on the front spacer...


Had some weird double-post. The website stops responding from time to time for me.

Yup, the visual doesn't bother me so much--I can fix that.

Likewise on non-responsive--that happens to me a lot.

[Wolfman64]

Originally Posted by limeypride

Interesting... I've been wrestling with that solution especially since it only requires I replace 2 tires. The problem I face is there's no data and nobody at BMW willing to answer, "what is the tolerance?" Given that, I'm kinda stuck because getting it wrong is something likely to break some major drivetrain components (transfer case, etc.).

Each 4WD solution seems to be different--Audi's, for example, on my RS7P had a near-zero tolerance requiring a square setup where I ran 295s all-around--that was kinda like driving a bobsled on most freeways.

Which GTC are you referring to?

You're right. Didn't think about the AWD aspect of its. Even then I don't think it's an issue.

Factory 275/285 staggered setup: Difference in circumference: 1.1%
Your 285/295 staggered setup: Difference in circumference: 0.7%
275/295 staggered setup: Difference in circumference: 1.8%, so 0.7% more than factory.

The other option is to stay with the 285 in front, increase the spacer to 18mm since you mentioned the rub occurs on the inside liner. This pushes the wheel out 3mm which is close to the 5mm increase of tire width on the inside.

Here is the AMG GTC I was referring to
Nevermind. Upload window is going blank when pressing upload. It's in the garage...

[limeypride]

Originally Posted by Wolfman64

You're right. Didn't think about the AWD aspect of its. Even then I don't think it's an issue.

Factory 275/285 staggered setup: Difference in circumference: 1.1%
Your 285/295 staggered setup: Difference in circumference: 0.7%
275/295 staggered setup: Difference in circumference: 1.8%, so 0.7% more than factory.

The other option is to stay with the 285 in front, increase the spacer to 18mm since you mentioned the rub occurs on the inside liner. This pushes the wheel out 3mm which is close to the 5mm increase of tire width on the inside.

Here is the AMG GTC I was referring to
Nevermind. Upload window is going blank when pressing upload. It's in the garage...

That's an interesting point now that I understand what you means about increasing the size the spacers. I'll go take another look and see if that would work.

Thanks!

[Ehloo]

So what’s your thoughts about the race chip. Did you end up getting one?

Originally Posted by limeypride

That's an interesting point now that I understand what you means about increasing the size the spacers. I'll go take another look and see if that would work.

Thanks!

[limeypride]

Originally Posted by Ehloo

So what’s your thoughts about the race chip. Did you end up getting one?

Yes, I have them both installed simultaneously and can switch between them at will from my phone.

I needed to eliminate my traction problem to test them properly and, having now done that, I've got a rubbing problem so pulling 1/8th mile launches back-to-back doesn't feel wise so yet again I'm delayed. I'll try and fix the tire problem tomorrow one way or another

[limeypride]

A few interior pics when dark:

[Wolfman64]

Now play some music so that the speakers light up

[limeypride]

Originally Posted by Wolfman64

Now play some music so that the speakers light up

Ooooh, you're soooo right.

[limeypride]

Just another pic that I rather like:

[FSociety]

Paint color is sick!

[josec70]

Originally Posted by limeypride

That's an interesting point now that I understand what you means about increasing the size the spacers. I'll go take another look and see if that would work.

Thanks!

Running 275 / 295 with no issues on my M5C , 21" wheel setup w/ no issues.

I think Hockeytime's running same setup.

[limeypride]

Originally Posted by josec70

Running 275 / 295 with no issues on my M5C , 21" wheel setup w/ no issues.

I think Hockeytime's running same setup.

Thanks.

What's your exact tire front and rear?

[josec70]

Originally Posted by limeypride

Thanks.

What's your exact tire front and rear?

275/30 ZR 21
295/30 ZR 21

Mich PS4S

No issues with any rubbing.

[limeypride]

Originally Posted by josec70

275/30 ZR 21
295/30 ZR 21

Mich PS4S

No issues with any rubbing.

Looks AWESOME! Glad to hear that setup works.

What color is that, black, right? // private joke, folks

[josec70]

Originally Posted by limeypride

Looks AWESOME! Glad to hear that setup works.

What color is that, black, right? // private joke, folks

TY sir!!! Black, gray. Purple .... u remember the good ole days ..

[Wolfman64]

So did you fix the front wheel rubbing situation? What was the solution, if so?

[limeypride]

Originally Posted by Wolfman64

So did you fix the front wheel rubbing situation? What was the solution, if so?

Ordered bigger spacers as suggested. They were scheduled to arrive yesterday but were delayed; arriving Monday.

I'm also looking at going back to 275s front since others with F90s are already running that setup without causing the 4WD system to throw a hissy.

[limeypride]

Originally Posted by limeypride

Ordered bigger spacers as suggested. They were scheduled to arrive yesterday but were delayed; arriving Monday.

I'm also looking at going back to 275s front since others with F90s are already running that setup without causing the 4WD system to throw a hissy.

Resolved: 11mm rear and 15mm front. 295s rear and 285s front. I just had to wait long enough for the tire to file down the inner wheel arch. Perfect now.

[limeypride]

Originally Posted by limeypride

Resolved: 11mm rear and 15mm front. 295s rear and 285s front. I just had to wait long enough for the tire to file down the inner wheel arch. Perfect now.

Tints done today (lost my patience so Coronavirus-defensed up, I ventured out):