E92 M3 BBK Post installation (HELP!)

[AP-M3]

BBK KIT - https://www.ebay.com/itm/14549518008...mis&media=COPY

Good afternoon,

Just installed a set of Retrofit Brembos from a Porsche Cayenne and they look great…but that’s about it.

-RBF 600 Brake fluid flush was done with the installation. (Only 2 bottles were used)

Problems
-I lost my function to be able to use the parking brake

-Initial drive after installation brake pedal feel was extremely soft and I didnt begin to bite until I was 40% into the brake pedal.

-Upon bedding in the brakes after 3 hard stops from 60-10 the brake pedal became incredibly stiff…i would really have to dig into the brakes to come to a stop and honestly it wasn’t anything impressive.

-Towards the end of the bedding process on the 8th stop again extremely stiff like i’m pressing into a brick wall and i’m still stopping but it did not feel confident aspiring at all!

Any tips would be appreciated thanks!

EDIT SOLVED

-To fix the parking brake you have to remove the rotor and get to the emergency brake system and increase the width of the drum brakes to fit the new calipers to engage the parking brake

-Conducted another brake fluid flush on all calipers and pedal feel is a lot firmer.

-Looks like the problem is with the brake pads..well I may have been a little too aggressive on the bedding process and glazed the pads lol

-Ordering Hawk DTC 80 PADS and will give a final review of the BBK

[Redd]

Shouldn't you be asking these questions to the vendor you bought it from?

I would put back your stock brakes just to make sure there are no problems with the ABS/DSC pump, brake booster and master cylinder. If everything works as it should with the stock calipers then your possibilities are:

1. Soft pedal - air in system but you seem to have fixed that. Mismatched caliper pistons (too large) can also cause a soft pedal as more fluid needs to be displaced to get the same travel on the piston.

2. Extremely stiff but no stopping power - this could be the pads

These are all questions you need to take up with your vendor.

[M3SQRD]

Why did you lose your parking brake? A picture of the rotors shows there’s a parking drum on the backside of the rear rotor hats. Is the parking brake drum not the correct diameter for the shoes?

A long brake pedal could be due to air still in the brake lines and/or air in the ABS/DSC system. Additionally, if the piston areas in the new kit brake calipers are much larger than the stock caliper piston areas, you’ll get a pedal with a really long travel before the pads clamp down on the rotors. Once the pads finally clamp the rotors, you should get good braking performance at that point. Air in the system and/or ABS/DSC system can be addressed with further brake bleeding and/or cycling of the ABS/DSC system. However, there’s not much you can do to address the long pedal if it’s due to mismatched piston areas.

A rock solid brake pedal that requires absurdly high pedal force typically is due to the piston areas of the new kit calipers being too small compared to the stock caliper piston areas. There’s nothing you can do to address this. It doesn’t sound like it’s the pads because you’d get bite from the pads after a long pedal.

It’s strange that you’re getting both a long pedal and a rock solid pedal. Can’t explain that one.

I’d recommend returning them or talking to your CC company because it sounds like you were sold a kit not properly developed for the e9x M3. The add is also misleading by saying things are “new” and still in “sealed packaging” yet then they say “refurbished/powdercoated” Brembo calipers. In the pictures, the powdercoating/painting appears to have been applied directly to existing painted calipers, not bare calipers.

[AP-M3]

Originally Posted by M3SQRD

Why did you lose your parking brake? A picture of the rotors shows there’s a parking drum on the backside of the rear rotor hats. Is the parking brake drum not the correct diameter for the shoes?

A long brake pedal could be due to air still in the brake lines and/or air in the ABS/DSC system. Additionally, if the piston areas in the new kit brake calipers are much larger than the stock caliper piston areas, you’ll get a pedal with a really long travel before the pads clamp down on the rotors. Once the pads finally clamp the rotors, you should get good braking performance at that point. Air in the system and/or ABS/DSC system can be addressed with further brake bleeding and/or cycling of the ABS/DSC system. However, there’s not much you can do to address the long pedal if it’s due to mismatched piston areas.

A rock solid brake pedal that requires absurdly high pedal force typically is due to the piston areas of the new kit calipers being too small compared to the stock caliper piston areas. There’s nothing you can do to address this. It doesn’t sound like it’s the pads because you’d get bite from the pads after a long pedal.

It’s strange that you’re getting both a long pedal and a rock solid pedal. Can’t explain that one.

I’d recommend returning them or talking to your CC company because it sounds like you were sold a kit not properly developed for the e9x M3. The add is also misleading by saying things are “new” and still in “sealed packaging” yet then they say “refurbished/powdercoated” Brembo calipers. In the pictures, the [...]

-No idea why I lost the parking brake..makes no sense to me.

-Yes i’m going to rebleed the whole system again tommorow and give an update.

-I only got the rock solid pedal feel after aggressive braking. Other than that normal driving it’s just extremely soft..having to press 70% into the brake pedal before it brakes and when it does it doesn’t feel confident it feels like I have drum brakes on🤣

-I’ve seen other people put this kit on and have no problems..if this problem persist i’m going to have it returned.

Thanks for your reply I greatly appreciate it!

[omgzirra_exe]

it should work directly, i can almost bet the shoes / spring are not seated properly. just remove the rear wheels and re-do the installation or just go over it again.

[M3SQRD]

Originally Posted by AP-M3

-No idea why I lost the parking brake..makes no sense to me.

-Yes i’m going to rebleed the whole system again tommorow and give an update.

-I only got the rock solid pedal feel after aggressive braking. Other than that normal driving it’s just extremely soft..having to press 70% into the brake pedal before it brakes and when it does it doesn’t feel confident it feels like I have drum brakes on🤣

-I’ve seen other people put this kit on and have no problems..if this problem persist i’m going to have it returned.

Thanks for your reply I greatly appreciate it!

Got it. So you may have overheated the pads and they faded when you couldn’t slow down without standing on the brake pedal. However, either you have significant air in the brake lines and/or air in the ABS/DSC system (can only get this air out by using ISTA to cycle the ABS/DSC pumps) or the new caliper piston areas are too large compared to stock caliper piston areas. I know you’re aware of other people installing this kit but there’s a chance similar calipers, or even identical calipers but with different piston sizes, were included in your kit.

When it comes time to buy new rotors and pads do you know where you can get replacement rotors? Pads? Did they at least give you the pad shape FMSI number or the pad part number and manufacturer? It’s important for a brake kit to know where you’re able to get consumables.

[AP-M3]

-Yeah not a lot of information in regards to rotor/brake pads etc…

-Going to perform another flush like I said and hopefully it’s not the ABS system👍🏽

Thank you!

[amrazM]

Are you bleeding both sides of the caliper?

[AP-M3]

Originally Posted by amrazM

Are you bleeding both sides of the caliper?

I didn’t do them myself i’m going to the shop tommorow and making sure they did that! But that’s a possibility. Thanks!

[liverpoolreds8]

Wow, those looks amazing!

[AP-M3]

Originally Posted by liverpoolreds8

Wow, those looks amazing!

Thank you! If I could do it again I would source the calipers on ebay from a 04-10 Cayenne and just have a local shop repaint/refurbish them. Feel like that would make more economical sense just a little less convenient!

[akamal92]

Is this an 18z brake kit? If so I just did my kit and running into all the same issues and resolutions but my front right caliper is rubbing the rotor did you run into any fitment issues besides having to trim dust shields?

[AP-M3]

Originally Posted by akamal92

Is this an 18z brake kit? If so I just did my kit and running into all the same issues and resolutions but my front right caliper is rubbing the rotor did you run into any fitment issues besides having to trim dust shields?

Beautiful car man! And I have the 17z brake kit. No figment issues in regard to the rotor I know the 18Z is fitted for bigger rotors but that’s as far as my knowledge goes unfortunately. And how do you feel about the brake pads? They have been the most unsatisfactory part of the kit so far.

[akamal92]

Originally Posted by AP-M3

Beautiful car man! And I have the 17z brake kit. No figment issues in regard to the rotor I know the 18Z is fitted for bigger rotors but that’s as far as my knowledge goes unfortunately. And how do you feel about the brake pads? They have been the most unsatisfactory part of the kit so far.

Thanks I’ve put a lot of work in the car last month I have the stock Brembo pads that come with the kit. I got my kit from
RCTuning shop I haven’t got to stand on them yet due to the rotor and caliper issue plus I’m still working out other things as I just dropped in an ESS G1 plus kit on the car along with a ton of other mods

[omgzirra_exe]

eeeheheheh so i was right on the rear shoes :P

glad you got it sorted.

[AP-M3]

Originally Posted by akamal92

Thanks I’ve put a lot of work in the car last month I have the stock Brembo pads that come with the kit. I got my kit from
RCTuning shop I haven’t got to stand on them yet due to the rotor and caliper issue plus I’m still working out other things as I just dropped in an ESS G1 plus kit on the car along with a ton of other mods

Absolutely mint…dream build🤌🏽

[M3SQRD]

Originally Posted by akamal92

Is this an 18z brake kit? If so I just did my kit and running into all the same issues and resolutions but my front right caliper is rubbing the rotor did you run into any fitment issues besides having to trim dust shields?

How is the rotor hitting the caliper? Is the caliper radial positioning too short so the rotor OD hits the caliper? Is the pad sitting properly on the rotor; i.e., pad not extending beyond the rotor OD (pad overhang) and/or not sitting lower than the rotor OD(rotor overhang)? It’s only on one of the fronts? That’s odd. Brake caliper brackets are mirror images of each other. Mounting hats are identical. Rotors are identical. It has to be an incorrectly designed or manufactured caliper bracket.

It could be the angle of your picture but the upper part of the pad looks like it’s closer to the mounting hat than the bottom part of the pad?