[blau3er]

Hi all,

I've posted various comments about the theory of this working. I don't own a G20 (or any G series for that matter) but I have wanted to see this through, so I picked up a set of F95 brakes today and tested it out on a G20 wheel hub I bought a few years ago.

I have previously confirmed that F97 X3M brakes are bolt on fitment to G20 (using the 395mm ///M disc, and 395mm 4 pot calipers). However this set up takes it to the next level with the 6 pot Brembo fixed bridge caliper.

The F95 X5M uses the same caliper body as the F90 M5, G80 M3, G87 M2 etc - however the key difference is that it uses a steel radial mounted caliper bracket, as the X5M hub does not have studs on it like all of the other current ///M cars. It also uses a 395mm disc (like the M5) and not the smaller 380mm disc that is found on the G80 etc.

This means that the caliper and disc mount directly onto the G series hubs (G20 G30 G11 G05 etc etc) and essentially provides a plug and play OEM BBK. The only consideration is that the disc retaining screw does not line up with the non-M hub, which really would be a non-issue once everything was bolted down and torqued to spec.

Just need to decide if I'm selling these or putting them in storage for when I eventually buy myself a G21 LCI Touring!

I also have the X5M rears, but I don't have a G2x hub to test it out on..... yet!

Pics:

[mwinemil]

This is awesome. What do you have invested thus far?

[blau3er]

A fairly tidy sum! I think you could expect to pay around £2500 GBP for a set up like this (front and rear).

However, that is still a fraction of a Brembo GT for example!

[blau3er]

This caliper set up is also bolt on fitment using the plain, blank 395mm non-M disc, if budgets are not allowing for the full ///M disc.

[prostcfc]

What kind of wheels are you going to need to even clear these?

[blau3er]

Originally Posted by prostcfc

What kind of wheels are you going to need to even clear these?

20" or some 19".

F90 M5 has factory 19" wheel options. It will all depend on barrel clearance.

I have 400mm under 19" on my F31 for example.

[Fudz]

I did something similar many years ago with a set of Audi TT discs and calipers on a Polo ( 312mm) .

The OEM parts bin always has an upgrade hidden, good work - now find out if they fit in a 792M wheel and i'll have them lol

[prostcfc]

The other thing with this, and I'm not sure how much it matters, but when you move from M Sport to M Performance on the M340i, you're supposed to go through ISTA and reprogram the ABS/DSC so it knows about the larger calipers. I would assume that doesn't exist for this application, or any true BBK, so what are the impacts, if any? I suppose ABS and/or DSC not operating as efficiently/effective as it could?

[Fudz]

Like you say when you fit Alcons or Brembo GT what do you do? How does the car allow for worn tyres, worn discs/ pads, 3rd party discs and pads? It's calculated thousands of times a second via the wheel speed sensors and adjusted by the ABS controller surely ?

[prostcfc]

Originally Posted by Fudz

Like you say when you fit Alcons or Brembo GT what do you do? How does the car allow for worn tyres, worn discs/ pads, 3rd party discs and pads? It's calculated thousands of times a second via the wheel speed sensors and adjusted by the ABS controller surely ?

Sure, but then why is there a procedure in ISTA for M Sport to M Performance?I doubt it’s there for no reason.

[Fudz]

I would love to know myself what it does

[Fudz]

I found this post on the F30 forum

12-31-2013, 05:18 AM #3
Serpent720
Private
47
REP
66
POSTS

Drives: F31 328i
Join Date: Apr 2013
Location: Hong Kong

iTrader: (0)

I think I need to at least answer this question.

I had the MP brake without SPBR for 2 weeks, the brake felt mushy, even would think that the stock brake feel was better. So did the DSC code to enable SPBR.

The difference are:
1. The mushiness at the initial braking is gone.
2. Feel like the original stocks brake feel at the initial braking, when pedal it down a little more, more bite and deceleration are much better than without DSC Code.

[blau3er]

Originally Posted by prostcfc

The other thing with this, and I'm not sure how much it matters, but when you move from M Sport to M Performance on the M340i, you're supposed to go through ISTA and reprogram the ABS/DSC so it knows about the larger calipers. I would assume that doesn't exist for this application, or any true BBK, so what are the impacts, if any? I suppose ABS and/or DSC not operating as efficiently/effective as it could?

An M340i with the track handling pack gets 374mm calipers, which are the exact same as the M Perf brakes. Without, it gets the smaller 348mm calipers.

The piston sizes between 348mm and 374mm calipers do not change, so coding is not likely to make any tangible difference at all to the brake pedal.

The key is ensuring the brakes are properly bled.

[daverdfw]

I have stock brakes, the nasty silver ones. Would love to even get the M Sport ones, I see the M Performance kits, but none come with an upgraded Master or Booster, I am reading conflicting info on whether I would need that.

[currahee]

Originally Posted by daverdfw

I have stock brakes, the nasty silver ones. Would love to even get the M Sport ones, I see the M Performance kits, but none come with an upgraded Master or Booster, I am reading conflicting info on whether I would need that.

there is a new kit number with the upgraded master+booster
3410 8 857 048

guess u have to check the part number of your master cylinder and booster to be sure if u need it. but was told likely the booster needs to be changed. some brake workshop mentioned no needed, just need coding.