Yet another BBK thread ..E89 specfic…

[pbondar]

So most of the parts arrived for the ‘small’ BBK for the rear..

F10 series calipers and E60 series disks…these rears are bigger than my current 6 pot Brembo front disks..

The F10 series caliper just looks like an upscaled copy of the E89 version.

Done a first paper mock up of a possible bracket to join these to the E89 chassis.

Not only is the disk much bigger 345 vs 300 or 324 for non 35is / 35is but the depth of the swept area is bigger..pic shows an E89 rear pad (same pad on both 300mm and 324mm rear discs) vs the E60 pad..

Autodoc do a cute trick with TRW ..they sell a ‘remanufactured’ real caliper for about a 1/5 of the price of an E89 caliper..

One caliper bracket wasn’t available in TRW OE supplier so bought a pattern part..interesting to see the myriad of differences…hopefully it will work ok..

 

[pbondar]

So reflecting on the various issues I bit the bullet and bought a couple of old rear hubs and bits with a view to being a lot easy to faff around with bits off the car rather than on..

A few head scratching hours playing with the old bits and my new bits…plus lots of washers, spacers, bolts..

As Meatloaf would say 2 out 3 ain’t bad..however in this case you need all 3 things to work for it to be a viable solution..

These parts are for a 345 mm disc with a 44mm piston sliding caliper solution..roughly based on a 5 series non M

I’ve got a set of M5 rear calipers coming with the option of a 370mm or 380mm rear disc….

New disc is 345mm vs an old E89 300mm disc from the non 35i/35is E89s…

 

[pbondar]

First trial fit of the 345mm E60 discs with F series 5 caliper and my first attempt at a bracket ..looks pretty ok..

 

[Armando1969]

Hi Peter,
I hope that you get what you are aiming at, but my guess is that when you count all the cost at the end. The PB/Ceika option probably won't be far off in cost and les hassle. But I applaud you for trying.

 

[pbondar]

Hi Peter,
I hope that you get what you are aiming at, but my guess is that when you count all the cost at the end. The PB/Ceika option probably won't be far off in cost and les hassle. But I applaud you for trying.

Ignoring R+D...the 'production cost' of a set looks to be round £750 max..against a current price of over £2,500 for a 345mm solution from Ceika or PB..of course not as sexy looking..but..cosmetically having a Ceika/PB on the rear really means you need there front BBK to match..or as I being fussy?

 

[Armando1969]

Ignoring R+D...the 'production cost' of a set looks to be round £750 max..against a current price of over £2,500 for a 345mm solution from Ceika or PB..of course not as sexy looking..but..cosmetically having a Ceika/PB on the rear really means you need there front BBK to match..or as I being fussy?

Hi Peter,
One question how do you get to £2500, OK its without shipping and taxes but I get for both Ceika and PB-Brakes quotes for around £1800 for the simple 345mm option.

 

[pbondar]

Hi Peter,
One question how do you get to £ OK its without shipping and taxes but I get for both Ceika and PB-Brakes quotes for around £1800 for the simple 345mm option.

See pic ..the PB in 345mm same size disc..yes I know more pistons ..is £2,008

Plus in this case 20% vat 5% duty so that one is £2,500

My prices for ‘my kit’ were inc vat and taxes and delivery

 

[pbondar]

Ok looking at a 370mm option now

Did get some F10 M5 calipers , bigger but they just won’t work without the £450 M5 380mm specific discs

And the pads are the same anyway ..but mount points the same for 35is F series 5 and M5 calipers

 

[pbondar]

As I tried to use a 4.5" angle grinder to take my left index finger off I thought I'd wash the blood off the old stock E89 rear brake pads..

So here you are..

Top row..left to right

Stock E89 non N54 pad for 300mm x 20 rear disc 42mm piston (US market 35i)
Stock E89 N54 pad for 324mm x 20 rear disc 42mm piston
Stock F 5 series pad for B21 345mm x 24 rear disc and hopefully 370mm x 24 rear disc 44mm piston

Bottom row left to right

Front pads

Stock M Sport pad as used in 340mm 370mm and 380mm x 30mm F and M2 M4 series front dual piston calipers 2x 44mm piston
Pad for upcoming front BBK Brembo 6 pot for use with 380mm x 30 mm F series M2 M4

 

[pbondar]

The F01 7 series rear discs arrived..

Found a UK company selling high carbon content drilled discs to match my 380mm M2 M4 fronts..

So it turns out for the 370 rear disc two options exist..

Either you can use my 345mm caliper carrier bracket adapter with a F series M5 caliper carrier OR…await the second 370mm specfic bracket ..that uses the F series 5 550i carrier bracket…

In both cases the caliper bracket needs machining..not that the required machining is difficult to be done at home.

The rear caliper in all cases is the F series 5 550i caliper..

I’ll fit the 370mm rears to match my 380 M2/M4 discs mated to the Ford Mustang GT350 Brembo 6 pot calipers…this will keep the front / rear brake ratios in the correct area..

Price for 345mm or 370mm discs are around £150 for a pair…caliper carriers are around £50 ish and calipers can be had for £50.these are all new prices..so a rear brake kit kit for £350 plus the price of my brackets..

Pics show stock rear Z4 300mm disc and 345 mm and 370mm disc options..

 

[pbondar]

I’ve moved the discussion back to this thread to try n tidy up the thread..so go there for latest updates

E89 - Z4 4-corner big brake upgrade with Brembo m-sport calipers

Great thread! If you happen to still have your stock 325M wheels, do they fit in front with the 370mm setup? Just to follow up, I had some brake maintenance to do on my e90 335 and while the calipers/rotors were off, I mocked up the S2NHA caliper and tried to install one of my e89's 325M...

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