Upgrading brakes, what to do about the rear?
- Thread starter InnovativeAuto
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3.5i rotors are lighter because they are 2 piece so there is some weight saving. I do not believe you can get them drilled or slotted. Not much difference in braking performance as outer rotor surfaces and volumes are same so rotary inertia of rotors is effectively the same.
Hello! I'm here. The parts are still in the CNC. The calipers are in the paint shop.
I have also ordered a 550i clutch disc and a new OEM DMFW (i cant found a better option in the DMFW side).
A new bearing kit has also been necessary for the M-FACTORY differential. Bad support from the dealer in UK.
I'll wait until everything arrives to mount it.
If all works ok in my car we can sell the adapter kit if someone have interest. i dont know the cost at the moment.
Regards!
Hi Fran,
I'm currently running PB BBk, 380 f/r with 8 pot f, 6 pot r. So far they have been great, and truly have paid for themselves on multiple occasions. That said I do notice the initial pedal feel is slightly longer/ softer compared oem, but the bite is there when you need it. I'm thinking the extra pistons maybe too much for the oem master cylinder. Have you looked into upgrading this as well, or have any thoughts? Honestly its not an issue in terms of safety, and the upgrade is more for a refined pedal feel.
Hi JTS. I still havent mount the brakes so i cant give you my feedback but a member of e89zpost (baaqaf) tell me that probably i will need to change the brake slave cylinder. Im waiting for the pieces. When i mount it i will post here my impresions with the OEM cylinder.
I think 1-2 weeks more. My mechanic is not the fastest in town.
Regards!
I think 1-2 weeks more. My mechanic is not the fastest in town.
Regards!
Do you know if it was just the F series unit, and if any mods were needed? If plug and play that would be amazing but as we all know the e89 is a damn unicorn and requires extra work.
Without checking the part #s, if the 335i MC is the same part or fits on a E89 then the E9x M3 MC will fit. Same externally, different internally.
Hi everyone.. finally today the front brakes from the M5 are mounted. The rear stock 19' wheels have smaller interior and the rear brakes dont fit. Probably i will change for a set of Apex wheels.
The feel of the pedal is worst than before. The master cylinder from a m5 f10 dont fit
. Please, @LMB335is can you help me with the parts you use to upgrade your master cylinder? i cant found the post .
Thanks!
The feel of the pedal is worst than before. The master cylinder from a m5 f10 dont fit
. Please, @LMB335is can you help me with the parts you use to upgrade your master cylinder? i cant found the post .Thanks!
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I just used a E9x M3 master cylinder. Plug and play. Same dimensions externally but holds a greater volume of brake fluid.Hi everyone.. finally today the front brakes from the M5 are mounted. The rear stock 19' wheels have smaller interior and the rear brakes dont fit. Probably i will change for a set of Apex wheels.
The feel of the pedal is worst than before. The master cylinder from a m5 f10 dont fit
Thanks!
What matters when upgrading master cylinders is bore sizes for front and rear brakes, not volume. I just upgraded my E89 with an M2 sport performance brake kit, 370mm x 30mm front rotors with Brembo 4 piston M calipers. BMW Z4 brake pedal travel and feel even when stock is terrible. Too much travel and no sensitivity. I'm working on MC upgrade now. X3 MC has much larger bores for both front and rear brakes which will provide much harder, shorter travel pedal. I'm in process of mocking up this set up on bench now. Will publish results as soon as I come up with workable combination.
Wrong choice of words on my part. It pushes more fluid, in effect more volume because of the bigger bores.
@Asbjorn
@LMB335is mentioned that on e9x we use the e9x m3 master cylinder as an upgrade. If the Z uses the same master as e89 you could do the same. seems like they aren’t the same and the Z really is a unicorn! The other thing to mention is when bleeding brakes on RHD e9x the furthest brake is actually on the rear drivers side of the car. The right hand drive z may have the same brake line routing and it might pay to check.
the ABS pump complicates matters as well and if not bled properly it could be causing you bad peddle feel. Need to use Bmw standard software tools and bleed the system using the ABS pump.
@LMB335is mentioned that on e9x we use the e9x m3 master cylinder as an upgrade. If the Z uses the same master as e89 you could do the same. seems like they aren’t the same and the Z really is a unicorn! The other thing to mention is when bleeding brakes on RHD e9x the furthest brake is actually on the rear drivers side of the car. The right hand drive z may have the same brake line routing and it might pay to check.
the ABS pump complicates matters as well and if not bled properly it could be causing you bad peddle feel. Need to use Bmw standard software tools and bleed the system using the ABS pump.
What @aus335iguy said. The M3 master cylinder is a E9x only item AFAIK. Hell they're not even interchangeable between RHD and LHD. Are you doing front and rear brake upgrades? If you're just doing the front you should be fine as is, if adding the rears then you might have a soft pedal.
I already have upgraded brakes. See attached excel sheet. Six pot front and six pot rear. However the total piston area was only increased up front, so the rear upgrade does not increase the pedal travel. My pedal travel is fine overall, and brake feel is awesome, although slightly longer than OEM. I use race pads with higher friction, so they bite quite hard. I just wanted the upgraded brake cylinder for increased safety margin on track.
