11" ET44 vs GT4 11" ET30

[erictrainer]

Paging CanAutM3

Pretty sure the M4 has more room in the rear than the M3, can you please verify?

[Spun Crankhub]

Originally Posted by SYT_Shadow

You think you could have fit a 10mm spacer and still been good on the outside?

I've got the Nankang AR1 315/30 on the 11 ET44 and have the 10mm spacer to clear the inside, with no problem on the outside. Also lowered on KW CS -2.8 camber.
Going to try the DH's soon that fanatic1 mentioned having a problem with.

[CanAutM3]

Originally Posted by erictrainer

Paging CanAutM3

Pretty sure the M4 has more room in the rear than the M3, can you please verify?

My understanding is that despite being slightly less wide at the max, the overall shape of the rear fenders of the M4 actually allows for more inner clearance than on the M3

[CanAutM3]

Another point of consideration is that the M4 GT4 does not have fender liners, which improves clearance (and saves weight).

[F3IGHTY]

Originally Posted by RSXDC5

I think a crucial piece of info is that you were trying to fit a 325/30 on an 18x11 +44 @ -2.7 rear camber. Comparing against my personal setup, you run -0.7 rear camber more than me, why not dial out some rear camber and get a wider rear wheel (the wider rear should help with sidewall deflection)...then apply a small spacer if needed.

Also of note, the 18x11 +30 gt4 wheel works in the rear because bmw was forced to compensate for crap fitment by reducing all suspension arm length by around an inch. My f80 friend with Ohlins ttx shared his original gt4 wheel fitment (315/30/18 r888r) pics with me and it literally pokes out by an inch or so...he had to get the e90 version of his SPL arms to allow fitment.

The shorter LCA / tension rod is only in the front. The rear will fit without much issue, especially using a 295 which is close to what the GT4 uses. I ended up pulling the rear hubs in slightly, (5-10mm) using a combination of LCA eccentric lockouts and spl upper links - all to run a 315/30 cleanly.

Before and after shown here:

[F3IGHTY]

Originally Posted by CanAutM3

Another point of consideration is that the M4 GT4 does not have fender liners, which improves clearance (and saves weight).

That picture clearly shows the fender liners though? I’ve seen most teams running them, the potential air water heat exchanger damage is pretty high if removed- let alone all the other electronics close by.

[m4AY]

the gt4 uses fully adjustable and shorter control arms and tie rod ends in the front, plus a huge 25mm or 32mm front spacer to fit the 18x11 et30 wheel, the rear also has all the fully adjustable arms, but not sure if they are shorter to fit the wheel, but comparing part #s to my regular m4, the front knuckle is the same, its the shorter arms and wheel spacer that allow for the wide wheels.