[fuxshiba]

M4's Brembo brakes on my F33 (420d SE from 2015), apparently custom made adapters needed?

I am new to this, would love some help from the pros out here.

As preparation, I have already upsized my wheels from stock 17" to 19" to fit the M4 brakes which I luckily got from someone who decided to upgrade his brakes of his fairly new M4 (only covered 3000 miles).

I was dumb enough to think they could fit right on, without doing too much research. And clearly they didn't fit. Apparently some custom made adapters are needed.

Any thoughts and recommendation?

Much appreciated.

[teaston]

The calipers will fit straight on (they are the identical calipers which are in the F3x M Sport brakes) but you need to get 370mm discs to fit. The holes on the M4’s hubs are 10mm further out to allow these calipers to fit the 380mm discs.

[LaNcE01]

Originally Posted by teaston

The calipers will fit straight on (they are the identical calipers which are in the F3x M Sport brakes) but you need to get 370mm discs to fit. The holes on the M4’s hubs are 10mm further out to allow these calipers to fit the 380mm discs.

So does that mean that all is required is to get the Fx 370 rotors to install them?

[doncarlyon]

My eyes hurt looking at those wheels

[aquazi]

Originally Posted by doncarlyon

My eyes hurt looking at those wheels

Look like BBS LM reps/ style... looked ok with a nice rear dish on the Golfs 10 years ago.. dont really suit the F33

[teaston]

Originally Posted by LaNcE01

So does that mean that all is required is to get the Fx 370 rotors to install them?

Correct, best to get TRW or Brembo 2 piece ones from Autodoc or similar.

[fuxshiba]

Originally Posted by teaston

The calipers will fit straight on (they are the identical calipers which are in the F3x M Sport brakes) but you need to get 370mm discs to fit. The holes on the M4’s hubs are 10mm further out to allow these calipers to fit the 380mm discs.

Thanks, the brake kit I got comes with 370 rear disks and front 380 front disks (very mean looking). Do you think its worth custom making the adapters for calipers to compensate the 10mm? Cheers

[fuxshiba]

Originally Posted by doncarlyon

My eyes hurt looking at those wheels

Now you hurting my feeling. It was indeed a lot of effort to get hold of these rotiform for my bolt pattern.

[R99]

The 380mm don't fit - nor do the 370mm rears....

You may as well sell the ///M discs and follow the advice on here to purchase 370mm fronts and 345mm rears.

There is someone I have seen on the FB groups that posted pics of 380mm ///M discs on his F3x but he did not post pics of the mounting solution and seemed to want to keep it guarded - not sure why, but maybe worth looking for the post and asking?

I avoided the problem entirely and had brackets made to fit F10 M5 6pots with 400mm discs!

[fuxshiba]

Originally Posted by R99

The 380mm don't fit - nor do the 370mm rears....

You may as well sell the ///M discs and follow the advice on here to purchase 370mm fronts and 345mm rears.

There is someone I have seen on the FB groups that posted pics of 380mm ///M discs on his F3x but he did not post pics of the mounting solution and seemed to want to keep it guarded - not sure why, but maybe worth looking for the post and asking?

I avoided the problem entirely and had brackets made to fit F10 M5 6pots with 400mm discs!

Such a shame, those M disks seem incredible and in great condition. If no other solutions found I will look into front 370 fronts and 345 rears. Thanks man!

[fuxshiba]

will handbrakes be affected by this modification?

[teaston]

Originally Posted by fuxshiba

will handbrakes be affected by this modification?

There’s different rear 345mm discs, ones for smaller handbrake shoes, and ones for the larger ones.

[doncarlyon]

This really is more work than its worth.

[fuxshiba]

Originally Posted by teaston

Correct, best to get TRW or Brembo 2 piece ones from Autodoc or similar.

So, in my case the blue M4 calipers came with fairly new Textar brake pads for their bigger M4 front and rear disks, would they need to be replaced for smaller pads to suit the smaller 370 front and 345 rear disks? (just trying to budget the whole thing as too many mistakes have already been made.)

Also are M4/M3 brake calipers definitely the same Brembo things as M Performance or M Sport calipers seen on other 3-4 series with M packages, which also have front 4 rear 2 pots, but with different colour variance?

Cheers.

[dizzy619]

I was under the impression that the m4 hubs were needed to fit the m4 full set up...

[teaston]

Originally Posted by fuxshiba

So, in my case the blue M4 calipers came with fairly new Textar brake pads for their bigger M4 front and rear disks, would they need to be replaced for smaller pads to suit the smaller 370 front and 345 rear disks? (just trying to budget the whole thing as too many mistakes have already been made.)

Also are M4/M3 brake calipers definitely the same Brembo things as M Performance or M Sport calipers seen on other 3-4 series with M packages, which also have front 4 rear 2 pots, but with different colour variance?

Cheers.

Yes absolutely the same pads fit, they are identical calipers, if you look on the back of them they say 370/380 on them.

[Watsey]

Originally Posted by dizzy619

I was under the impression that the m4 hubs were needed to fit the m4 full set up...

That's what I'd expect as well, but I may be wrong.

[R99]

Brake pads are identical between 340mm 370mm and 380mm.

///M are obviously a different compound from factory.

[fuxshiba]

Originally Posted by R99

The 380mm don't fit - nor do the 370mm rears....

You may as well sell the ///M discs and follow the advice on here to purchase 370mm fronts and 345mm rears.

There is someone I have seen on the FB groups that posted pics of 380mm ///M discs on his F3x but he did not post pics of the mounting solution and seemed to want to keep it guarded - not sure why, but maybe worth looking for the post and asking?

I avoided the problem entirely and had brackets made to fit F10 M5 6pots with 400mm discs!

came across this guy on a chinese forum fitting the same M brake kit from an M3 on to his F30 (b48).

He had to cut the brackets in order to mount the custom brackets so the the 380 and 370 ///M discs can be used.

seems hard work.

link to the post: https://www.xcar.com.cn/bbs/viewthre...2133263&page=4

[B58_Touring]

Surely the simplest solution is just to buy the correct discs for your car? Straight forward bolt on upgrade over what you have then. Sell the part worn M discs to offset the cost a little

[Eddamoo]

Not a chance in hell would I be using fabricated adapters to mount the calipers! Stick with a new set of discs or look at replacing the entire hubs. Hubs shouldn't be expensive, but you have to add M tax which will be undoubtedly astronomical!

[R99]

Originally Posted by Eddamoo

Not a chance in hell would I be using fabricated adapters to mount the calipers! Stick with a new set of discs or look at replacing the entire hubs. Hubs shouldn't be expensive, but you have to add M tax which will be undoubtedly astronomical!

Nothing wrong with using fabricated brackets - lots of calipers are a radial mounted design and use brackets from the factory.....

However, those brackets from China look rather dubious as it appears that the caliper body may have been machined to allow fitment