Rear wheels bottom out over bumps

[BasedSkarm]

I bought a neglected '01 m3 that I'm in the process of renewing. Over any bump the rear wheels will hit the fender and make a scraping noise. I've replaced the shocks, springs, shock mounts, and most bushings in the rear but the issue remains. The wheels are stock, with 275/40/18 tires. Any ideas on what could be causing this? Heres a pic where you can see the resulting marks on the tires.

[Zekarus]

stock is 255/40R18

[Nate047]

Yea the tire size is too wide and too tall. Get rid of those ASAP.

[BasedSkarm]

That was next on my to-do list. I looked at the tire size sticky here though, and it looked like 275s should fit in the back. Makes me wonder if there's something I missed.

[Cubieman]

Running PS4 275/35's on stupid low BC coilvers without issue, must be the offset of the aftermarket wheels and/or tire height that allows it to work.

[elbert]

That was next on my to-do list. I looked at the tire size sticky here though, and it looked like 275s should fit in the back. Makes me wonder if there's something I missed.

If you're running 275, the correct size is 275/35, not 275/40. The 275/40 is more than an inch taller than 35's.

[S54330Ci]

Are you running spacers?

[BasedSkarm]

If you're running 275, the correct size is 275/35, not 275/40. The 275/40 is more than an inch taller than 35's.

That explains why i thought the car was sitting about an inch too low thanks!

[S54330Ci]

That explains why i thought the car was sitting about an inch too low thanks!

That doesn't explain why your tire is rubbing against the fender arch assuming you are running on OEM wheels. Looks like it is poking out farther than it should.

[BasedSkarm]

Well its not on spacers, so it shouldnt be. Theres a bit of clearance on level ground, it doesn't rub normally

[S54330Ci]

Well its not on spacers, so it shouldnt be. Theres a bit of clearance on level ground, it doesn't rub normally

Well then there is something else going on with your rear suspension. Here is a picture of a 2001 M3. Note how inset the wheel and tire is relative to the fender lip. Has nothing to do with the tire's aspect ratio.

What does the driver's side look like? Any rubbing there?