Retrofit larger rear discs n calipers to non 35is E89s

[Anonymous]

Having gone down a route of first fitting 330mm 20mm 28i OE calipers on the front (20i 300mm 20mm) and painting both front and rear calipes in yellow and regretting it I've today completed the odessy.

I replaced the 330mm 28i 20mm discs and OE caliper with an E90 M3 BBK with 6 pots and 338mm 26mm setup

I did some research and saw that the 35i rear discs n caliper should be a straight bolt on..

So I bought some 35i 2nd hand calipers from the USA and had them expensively refurbiished in BMW gold by BiggRed only to discover that in the US the 35i (not the 35is) had exactly the same discs as the 18i!

So second attempt bought some European spec 35i(s) calipers, had them refurbished and today fitted to the Zed.

Got some Zimmerman 324mm by 20mm discs to replace the 300mm by 20mm OE versions.

Very pleased with the looks, feel and power of the set up..

I have a catalogue of pictures of different discs/calipers/colours if anyone ever wants to debate that one!

 

[Boltz]

Nice one Pete How much did it cost to put that rear brake set up together?

 

[Anonymous]

Hi Boltz..
Finding 35is/35is specific bits is hard work...

I bought the calipers in 3parts from 3 suppliers total price £180

Discs were £76

Pads to match fronts Textar £53

BigRed £225 (should have been £250)

Rear splash shields £45

3 hours labour £114

So £700 ish..

The main issue is the rear caliper newish is around £700 due to the electronic parking brake..

 

[Boltz]

Peter what are you doing with the US calipers you had refurbed? The reason I ask is that as you know I have the same front BBK kit as you but I have standard 18i rear discs and calipers, and you mentioned the US callipers were paired up with 18i discs so potentially they could fit my car.

 

[Anonymous]

Peter what are you doing with the US calipers you had refurbed? The reason I ask is that as you know I have the same front BBK kit as you but I have standard 18i rear discs and calipers, and you mentioned the US callipers were paired up with 18i discs so potentially they could fit my car.

Sound of a vulture croaking in anticipation of a good feast...



Well Boltz..funny you should say that..yes I’ve got a lovingly refurbished set of Phoenix Gold metallic calipers that will fit any E89 bar 35i/35is..

Plus brand new BMW OE discs and BMW rear pads plus new rear spray shields....kerching..

 

[Boltz]

Yes Peter I am perched on a branch looking down on the feast
So. I have a couple of options follow the path you have taken with the Euro calipers and bigger discs but would I get a worthwhile improvement in braking or do I be cheeky and feast on the US kit you have which will aesthetically match my front BBK kit nicely.

 

[sumotan]

Hi Phondar & Boltz Im also looking for a set of Euro 35i or 35is rear calipers to complement a BBK Front.
After reading about how Dsc functions, for me I think it should help in keeping the chassis in balance more.
Im thinking of going M series 4 pot calipers. if my resarch is correct the F30 etc series should be a pnp for our cars.
On another note I do wonder if the stock master brake cylinder is sufficient for the job.

Cheers

 

[Anonymous]

The situation is complex and not clear to me..

Aesthetically I'm very pleased with my lovingly and expensively created 35is rear brake job, the Zimmerman drilled discs set it of perfectly..all in the gold which I woundn't have chosen had it not been for the BBK in gold and it felt like a Philistine to overpaint those BBKs..

Two separate issues..when you look at the non 35is rear caliper it has a pad that is actually bigger in area than the the 35is pad!!

The disc is 24mm bigger in diameter but with a smaller pad..

So I assume it grips better but doesn't seem to me to be obvious /compelling that its going to be a big improvement except maybe in total mass..

Then the DSC...this is a whole pile of very clever capablities but its pretty imponderable as to what tinkering with it does, unless you have a private test track and want to spend days trying to work out what all the parameter codings do..

Its not like its some linear logical fashion..there are parameters you can toggle on and off but others have a range of parameters,,

What I do know is that the BBK kit worked fine with the stock rear calipers..it still works fine with the 35is rear calipers as well...maybe better, but I don't know as I put my new super duper all season tyres on and that's done a lot for grip..previously the ABS was triggering quite easy on cold wet/greasy roads..

Certainly with this BBK there seems no need to change the master cylinder..

Given that the DSC balances up the rears to avoid them locking up and biases the forces to maintain it, I'm loathe to tinker with what is undocumented changes..

Some other guys code off the wet weather wipe/e-diff etc but not sure what that gives a road based car?

 

[mcbutler]

All you need

1X Caliper housing left - 34116875649
1X Caliper housing right - 34116875650
2X Brake rotor, ventilated, front - 34106797603
1X (Set of pads) Brake pads asbestos-free - 34116878882
1X Brake pad wear sensor, front left - 34356792289

 

[sumotan]

Hi Peter,
Thanks for sharing your experience. Question pls aren't European 35i using the same F&R set up as the 35is ?
The slightly larger disc rotor with smaller pad like you say brakes better with better heat management
I think & perhaps functions in sync with whatever the DSC is program to do.

Cheers

 

[Anonymous]

Yes the European spec 35i and 35is share the same brakes, the US35is only has the same rear caliper./ disc..

The DSC is set up differently for the 35i as it it is for N20 variants and I think there is a change to cope with auto boxes but what those changes are and how material those changes are who knows..

On the original E90 where the front retrofit was an option there was a s/w BBK parameter change but again who knows what it effects..

Weight transfer for the N20s is less under heaving braking so again complex issues to model..

All I can say is that it all seems to work very well so far with much better high speed braking in terms of feel/power/rate of initial retardation..

 

[Boltz]

All you need

1X Caliper housing left - 34116875649
1X Caliper housing right - 34116875650
2X Brake rotor, ventilated, front - 34106797603
1X (Set of pads) Brake pads asbestos-free - 34116878882
1X Brake pad wear sensor

Or you could just buy the front BBK

 

[mcbutler]

All you need

1X Caliper housing left - 34116875649
1X Caliper housing right - 34116875650
2X Brake rotor, ventilated, front - 34106797603
1X (Set of pads) Brake pads asbestos-free - 34116878882
1X Brake pad wear sensor

Or you could just buy the front BBK

BBK ???????

 

[Anonymous]

34116878882

Mark, I think what Boltz was pointing out you can buy the BMW turnkey BBK for £1,200

The parts list you have adds up to about £1,200+£200+£50+£15+£30 ish = £1,500 albeit a slightly different config.

Depends whether you want a 6 pot Brembo set up with 338 /26 drilled/grooved/vented discs or a 4 pot OE set up with 370mm/30mm grooved and ventilated discs..

 

[Boltz]

Apologies Mark!!!!
Thanks Pete for clarifying why I mentioned the BMW Performance Front Big Brake Kit