135i Calipers Fitted to Z4M

[bradz]

Yeah available from Martin at MS MOTORSPORT.

No the stoptech ones dont have the problematic ceramic cap.

[Mangozac]

So I took the new brakes for the first proper test today and am pleased to report overwhelmingly positive results! A whole day and 600+ KMs blasting around the hills of northern New South Wales was a good workout. While the stock calipers have no issues at all with stopping, the 6 pistons had a noticeable amount more ugency to their stopping (most likely due to the slightly shortened pedal travel).

This wasn't on the track so there wasn't any opportunity to assess brake fade (even driving fast through winding hill roads just doesn't generate enough heat).

So all in all I'm very pleased with this upgrade!

[BMWZ4MC]

Sounds like a day we’ll spent
I’m sure you wouldn’t get fade on the track with this set up (as long as you use decent fluid) since the stock brakes will hold up to reasonable abuse. Was the pedal feel consistent throughout the day, hot and cold? As we’ve discussed before, that was what I found the OEM set up really lacked...
Good to hear it was worth the hard work

[Mangozac]

Was the pedal feel consistent throughout the day, hot and cold? As we’ve discussed before, that was what I found the OEM set up really lacked...

Yes, very consistent but I'd never really noticed inconsistency with stock brakes with this kind of driving.

[gnx]

Prompted by the recent thread discussing some brake options, I figured I should share my recently completed front brake upgrade.

I did a lot of testing with many different Brembo front calipers, testing blue calipers from an F82 M4 and F20 M140i. The M4 calipers can be made to work on E46 M3s, so the expectation was that they would work with the Z4M but alas the slight difference in steering knuckle meant it wouldn't work. The M140i calipers can be made to fit but would need a significant spacer so that the wheel spokes will clear the caliper.

In the end, I saw how nicely the E82 135i Brembo 6 piston calipers worked on another member's car and decided to stop giving myself headaches and go down the tried and tested route

I'm running the 6 piston Brembo fronts on the stock CSL rotors and the stock rear brake setup. Based purely on piston sizing calculations this will have adjusted the bias backwards slightly, however accounting for a more aggressive pad in the front I feel that there's no significant difference in the bias.

I had the new calipers and the stock rear calipers both painted a metallic blue, similar to the M4/M140i calipers, then M decals added and a clear coat. All high temp paint. At first I was unsure about drawing attention to the small real calipers, but justified it due to the fact that the F10 M5 has a similar setup: big, 6 piston calipers up front and little single pistons at the back.

20190514_103148.jpg

20190623_110448.jpg

20190623_110455.jpg

20190623_141641.jpg

20190616_161042.jpg

He best thing is that a new caliper bracket isn't even necessary! They bolt straight up to the knuckle with some 8mm spacers and longer mounting bolts (the mounting bolts from the 135i are perfect). The spacers are basically M12 washers 8mm thick and 32mm diameter - I machined mine from some 304 grade stainless round bar. I also fitted some braided steel brake lines to the front calipers while I was at it

How do they perform? Well I haven't had a chance to give them a workout with a hard drive yet, but for day to day driving they feel fantastic! The pedal feel is improved but also still very "BMW factory" feeling, if that makes any sense. Still very linear.

I am familiar of reports of the ceramic part of the pistons fracturing on these calipers but in the very few cases I've heard of it has been restricted to cars under heavy track use. I'm not concerned, but worst case they need rebuilding one day.

I'll have a better idea/confirmation of the performance in heavy use in a couple of weeks but so far is proving to be a very satisfying upgrade. They look amazing and give the Z4M a more modern feel.

These look like OEM M359 rims. Am I correct? Did you have to use spacers up front for them to fit? Anybody else can chime in perhaps?

[GT Spec]

Prompted by the recent thread discussing some brake options, I figured I should share my recently completed front brake upgrade.

I did a lot of testing with many different Brembo front calipers, testing blue calipers from an F82 M4 and F20 M140i. The M4 calipers can be made to work on E46 M3s, so the expectation was that they would work with the Z4M but alas the slight difference in steering knuckle meant it wouldn't work. The M140i calipers can be made to fit but would need a significant spacer so that the wheel spokes will clear the caliper.

In the end, I saw how nicely the E82 135i Brembo 6 piston calipers worked on another member's car and decided to stop giving myself headaches and go down the tried and tested route

I'm running the 6 piston Brembo fronts on the stock CSL rotors and the stock rear brake setup. Based purely on piston sizing calculations this will have adjusted the bias backwards slightly, however accounting for a more aggressive pad in the front I feel that there's no significant difference in the bias.

I had the new calipers and the stock rear calipers both painted a metallic blue, similar to the M4/M140i calipers, then M decals added and a clear coat. All high temp paint. At first I was unsure about drawing attention to the small real calipers, but justified it due to the fact that the F10 M5 has a similar setup: big, 6 piston calipers up front and little single pistons at the back.

20190514_103148.jpg

20190623_110448.jpg

20190623_110455.jpg

20190623_141641.jpg

20190616_161042.jpg

He best thing is that a new caliper bracket isn't even necessary! They bolt straight up to the knuckle with some 8mm spacers and longer mounting bolts (the mounting bolts from the 135i are perfect). The spacers are basically M12 washers 8mm thick and 32mm diameter - I machined mine from some 304 grade stainless round bar. I also fitted some braided steel brake lines to the front calipers while I was at it

How do they perform? Well I haven't had a chance to give them a workout with a hard drive yet, but for day to day driving they feel fantastic! The pedal feel is improved but also still very "BMW factory" feeling, if that makes any sense. Still very linear.

I am familiar of reports of the ceramic part of the pistons fracturing on these calipers but in the very few cases I've heard of it has been restricted to cars under heavy track use. I'm not concerned, but worst case they need rebuilding one day.

I'll have a better idea/confirmation of the performance in heavy use in a couple of weeks but so far is proving to be a very satisfying upgrade. They look amazing and give the Z4M a more modern feel.

These look like OEM M359 rims. Am I correct? Did you have to use spacers up front for them to fit? Anybody else can chime in perhaps?

I have the same Brembo/BMW Performance 6 pot callipers up front and I'm using 10mm H&R spacers to clear the 163M CSL rims.

[maupineda]

I have this setup and is perfecto for street and fast road driving. I paired them with Porsche 996 rears.

[B21]

FWIW I used those babies with some 348 mm discs on my 35is..very nice feel and action

[Meds]

I'm (very) slowly preparing for this upgrade on my 3.0si.
So, I'm gathering reading material and a parts list.
I have the calipers from my 130i (they were one of the 'Performance' parts option on the 130i)
I replaced all 12 pistons including seals. Then some threads helicoiled. Then a full strip down and refurbish in the original Pheonix Yellow they came with.
The calipers were wrecked when I found them on Facebook market place, of all places, they'd spent their life on 3 different track cars. 2 completely stuck pistons, all seals gone and just in a really poor state with knackered threads.

Here they are on my 130i after all the work:



I understand I need some different mounting brackets, hoses (available as a bundle from a Cutters member) and the CSL/Z4M discs.

[B21]

Great restoration!

[Meds]

Great restoration!

Yes, it was quite an emotional journey. Problem after problem.

The stuck piston was a nightmare. It took numerous workshops much pursuading to even get them to look at a process to remove it. they all immediately turned me away, telling me to buy a new caliper. They just didnt want the faff.

In the end, an old skool mechanic/engineer agreed to figure something out. He fashioned some super sketchy air compressor pipework that attached to the bleed nipple to force the piston out. It took him an hour of forcing air through it, and using numerous tools before getting some movement.
The single piece caliper design was the problem, if I could have broken the caliper apart I could have easily drilled that sucker out, or got behind it somehow..

The piston was heavily corroded and I suspect it was like that for years.

[B21]

Well done..I would have just paid the cash for a new set..

I've refurbished some calipers in the past..but even with refurbishment these days I use a professional outfit.

Hopefully they will work for you as well as they do for me!

[taz1966]

How much for a new set of these.
Or can anybody recommend where i can buy a set.
Had a look on eBay but can't find a set.

[B21]

How much for a new set of these.
Or can anybody recommend where i can buy a set.
Had a look on eBay but can't find a set.

£1,200 with a set of 348mm by 26mm discs for E90s

Yiu can but them from lots of places

Called BMW Performance Brake

[taz1966]

How much for a new set of these.
Or can anybody recommend where i can buy a set.
Had a look on eBay but can't find a set.

£1,200 with a set of 348mm by 26mm discs for E90s

Yiu can but them from lots of places

Called BMW Performance Brake

Thanks.
Are the discs a direct replacement on the ZMR