Z3 front brake frustration.

[e28Fan]

My 2000 z3 2.8 coupe's brakes have always been very dissapointing. I have always hoped to upgrade them and get better results. I believe now that my past brake upgrade experience was likely unique. I have upgraded 2 different E28's front brakes to E32 750il V12 calipers and rotors. The results were nothing short of mind blowing. I very badly want this stopping power in my Z3. After much additional research I now realize the E46 330ci calipers I just picked up will not give the same results because of the affect to the bias and things not being that simple. Nearly every post has multiple people saying why do you want bigger? Why do you need it? I do x,y and z with Zero issues. The only conclusion I can draw from this, is that there is something wrong with my brake system. I have replaced rotors, pads, and fluid. I had it professionally flushed/bled and have never been satified with the results. I can lock them up if need be, but the pedal feel is too stiff and feels like it requires too much pressure(work). The booster holds vacuum well and the brakes go nearly dead when vacuum is depleted. I am not really tracking, only the occasional auto x. It's time again for brakes and I would prefer to do this once. From what has been shared with me and that I have read, a BBK will largely only mitigate fading with prolonged intense driving. My driving never exceeds an auto x. I have never stepped up to any 'race' pads. The current feel and stopping power is just poor and almost any other car is better. I do not care about filling out the empty wheels for looks, I prefer to stay at 17" wheels. I just want gobs of stopping power. My car does have some additional weight in the front so this is a safety issue for me as well. I do appreciate that tires are an important factor. Any advice is greatly appreciated.
Thanks,
JC

[s8ilver]

How much additional weight, and from what? I wonder if you have a bad master cylinder or booster. Either can cause very hard pedal feel with not a lot of stopping power.

You also say you can lock them up. What tires are you running?

[ross1]

I'm wondering if some of the problem is simply glazed pads/rotors. Are you carefully(gently) bedding in the new parts?

[e28Fan]

How much additional weight, and from what? I wonder if you have a bad master cylinder or booster. Either can cause very hard pedal feel with not a lot of stopping power.

You also say you can lock them up. What tires are you running?

I am running probably about 70-80lbs? of ESS TS2 supercharger and heat exchanger. Brakes were the same before and after SC install. Tires are Goodyear Eagle 225/45/17. It has had Potenza RE-71R's on it and pedal feels the same. I will do some specific research on MC and booster diagnosing. Thanks!

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I'm wondering if some of the problem is simply glazed pads/rotors. Are you carefully(gently) bedding in the new parts?

Yes, I went through the recommended bedding procedure. The brakes were about the same as before I did them.

[bluptgm3]

PF has a ‘Z’ rated pad (0558.11) that is a high performance street pad. They still require a bit of heat to work well, you didn’t mention where you live. Hot days in Seattle are perfect for these pads.…and you didn’t mention what pads you are running.


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[e28Fan]

Thanks for the recommendation. Honestly, I don't remember what I installed, certainly wasn't anything notable. At the time I was just looking to get it drivable asap. Now, I am at the point where I am trying to educate myself on doing it right with the least amount of wasted resources. Thanks again.
JC

[Muzz258]

Attached is a file on brake upgrades from various forums. Hope it helps.

[e28Fan]

Thanks for the recommendation. Honestly don't remember what I installed, certainly wasn't anything notable. At the time I was just looking to get it drivable asap. Now, I am at the point where I am trying to educate myself on doing it right with the least amount of wasted resources. Thanks again.
JC

[e28Fan]

Attached is a file on brake upgrades from various forums. Hope it helps.

This is great, thank you!