Porsche Brembo 996 BBK conversion

[Nardo S54]

Apologies as I’ve not read all 36 pages but for the members who’ve been dealing with squealing, have you confirmed the rears were not installed backwards? Given the orientation on BMW’s (rear of rotor instead of front like Porsche), the calipers need to be switched between driver and passenger, and of course then bridge pipe must be installed on the opposite end. This was well documented in the original thread on the other site but only offer it up in case it got lost.

And if the rear orientation is not the issue, well perhaps this is par for the course lol

https://m.youtube.com/watch?time_continue=203&v=fUNHb9O52WQ&feature=emb_logo

[Mr.wReckless]

For what it's worth, I had my local garage blow out the pistons, I cleaned them up and put them in the freezer. The calipers went in the oven, and with some piston grease the cold pistons were super easy to slide into the warm caliper cylinders. New o-rings and dust boots of course.

Regards

[DoubleSidedTape]

From Apex: https://support.apexraceparts.com/hc...ance-e46m3.png

They indicate that an 18x9.5 +35 Arc 8 needs a 5mm spacer, but an EC7 will fit without one.

[repoman89]

I test fit my new TA16s yesterday and they have a ton of clearance. 18x9.5 ET35.

[DoubleSidedTape]

What wheels fit with no spacer in the front? I remember my stock 18 rears fitting, but I need a 10-12mm spacer with my arc-8 17x9.5 +35.

Ive heard that some apex wheels in 18x9.5 +35 will fit but not clear on arc8 vs ec7 and regular vs forged versions of those.

Any others?

[repoman89]

Just did my first pad change with these to my DS1.11 track pads in 15 minutes * chef's kiss *

No screwing around with clamps or anything, just use the old pads and some elbow grease to push the pistons back in. My Girodisc dust boots on the pistons are holding up perfectly so far too. Only about 15 sessions on them and some street driving (enough to eat through the stock Textars) but good to see they weren't unexpectedly shredded or anything.

[r4dr]

The ZCP rotors are 345x28mm, drilled, and floating. The stock rotors are 325x28mm, solid, and non floating. The ZCP rotors have more heat capacity, expel heat faster, and deal with heat better than stock. Not as much better as a good BBK rotor, but absolutely better than stock.

It's a little under 10% in increased thermal mass, from my napkin math. Nothing amazing, but every bit counts I guess. The co-cast construction is more "somewhat floating" based on what we've seen from similar designs.

I wish I could find ZCP rotors with solid faces.

[Arith2]

I was more responding to Arith2's allegations that I didn't know what I was talking about when it comes to heat management of braking systems. What he was talking about was wrong, about where and how heat transfers in braking systems. Also, the 996 brake caliper change does not improve heat capacity, which is what he claims.

Science is science and if you disagree, fine. The facts don't change. Don't take things so personally. I pointed out where you are wrong and you pointed out where you think I'm wrong. I don't know how that's personal.

[t44tq]

I was more responding to Arith2's allegations that I didn't know what I was talking about when it comes to heat management of braking systems. What he was talking about was wrong, about where and how heat transfers in braking systems. Also, the 996 brake caliper change does not improve heat capacity, which is what he claims.

[Obioban]

First point- if you're using the same ZCP rotor, you are limited by the dimensions of the friction surface. You can't really increase swept area, unless you get a long, curved caliper with a matching pad. 996 pads are rectangular and somewhat tall, so not the correct shape to increase swept area over the stock caliper. My point is, you're not effectively increasing swept area with the 996 setup- measure the swept area of the 996 pad versus the stock pad. I don't know the exact dimensions and don't care to look it up, but swept area is your limiting factor here.

Second- it's not an "imaginary barrier" that insulates a piston. If you look at a proper motorsports caliper's pistons, they are designed to prevent heat transfer from the pad to the caliper and fluid inside. Stainless steel (poor conductor) and vented.


Compare the image above to this one:


See the differences in the piston? The Porsche Brembo uses an aluminum piston, not vented, and the caliper has no venting either, compare to above.

My point is not that the ZCP rotor and the stock 325mm rotor have the same heat capacity- it's that if you compare the stock brake on the same ZCP rotor to the 996 setup, you're not gaining any heat capacity.

Brake pad backing plates are steel and are not designed to conduct heat- steel is a poor conductor. If they were supposed to conduct heat, they would not be painted, and would be made of aluminum, which is a far better heat conductor.

You can make personal attacks all you want, but it is clearly you who does not understand how good brakes work. Furthermore, if this setup requires more pedal travel, then you really need to change out master cylinders or you're actually _losing_ braking power. You're spreading around bad information, which people are taking as gospel. If you don't want to listen, sorry that you aren't willing to learn.

Heat capacity isn't really an issue with the stock brakes, much less the ZCP brakes, assuming track pads/fluids. The main benefits of a BBK on this chassis are faster pad swaps (996 retains), rigidly mounted caliper for better feel (996 maintains), longer pad life through bigger pads (996 retains), and longer rotor life (996 does not retain, but makes free, so it doesn't matter).

[t44tq]

Your thoughts are not scientific and you are literally trying to tell us more contact area doesn't matter because the piston is somehow insolated by some imaginary barrier. The backing a brake pad is metal, which is highly conductive. Losing material does not create friction, it's because of friction. Stop giving feedback about things you don't understand. A 30 minutes bit of research to understand the basics of thermodynamics will show you what I said is true. If you don't want to look it up, that's perfectly fine but please stop giving out objectively false information.

It's ok you don't think the 996 kit is worth it. That doesn't negate that it has better performance in regards to heat.

First point- if you're using the same ZCP rotor, you are limited by the dimensions of the friction surface. You can't really increase swept area, unless you get a long, curved caliper with a matching pad. 996 pads are rectangular and somewhat tall, so not the correct shape to increase swept area over the stock caliper. My point is, you're not effectively increasing swept area with the 996 setup- measure the swept area of the 996 pad versus the stock pad. I don't know the exact dimensions and don't care to look it up, but swept area is your limiting factor here.

Second- it's not an "imaginary barrier" that insulates a piston. If you look at a proper motorsports caliper's pistons, they are designed to prevent heat transfer from the pad to the caliper and fluid inside. Stainless steel (poor conductor) and vented.


Compare the image above to this one:


See the differences in the piston? The Porsche Brembo uses an aluminum piston, not vented, and the caliper has no venting either, compare to above.

My point is not that the ZCP rotor and the stock 325mm rotor have the same heat capacity- it's that if you compare the stock brake on the same ZCP rotor to the 996 setup, you're not gaining any heat capacity.

Brake pad backing plates are steel and are not designed to conduct heat- steel is a poor conductor. If they were supposed to conduct heat, they would not be painted, and would be made of aluminum, which is a far better heat conductor.

You can make personal attacks all you want, but it is clearly you who does not understand how good brakes work. Furthermore, if this setup requires more pedal travel, then you really need to change out master cylinders or you're actually _losing_ braking power. You're spreading around bad information, which people are taking as gospel. If you don't want to listen, sorry that you aren't willing to learn.

[Obioban]

A lot of people are under the misconception that this will improve your heat capacity, which is not correct. Since you have no manners I’m not going to continue engaging with you, but as an information sharing exercise, I posted my thoughts.

The ZCP rotors are 345x28mm, drilled, and floating. The stock rotors are 325x28mm, solid, and non floating. The ZCP rotors have more heat capacity, expel heat faster, and deal with heat better than stock. Not as much better as a good BBK rotor, but absolutely better than stock.

[COVID-19]

This brings back m3forum memories

[Arith2]

A lot of people are under the misconception that this will improve your heat capacity, which is not correct. Since you have no manners I’m not going to continue engaging with you, but as an information sharing exercise, I posted my thoughts.

Your thoughts are not scientific and you are literally trying to tell us more contact area doesn't matter because the piston is somehow insolated by some imaginary barrier. The backing a brake pad is metal, which is highly conductive. Losing material does not create friction, it's because of friction. Stop giving feedback about things you don't understand. A 30 minutes bit of research to understand the basics of thermodynamics will show you what I said is true. If you don't want to look it up, that's perfectly fine but please stop giving out objectively false information.

It's ok you don't think the 996 kit is worth it. That doesn't negate that it has better performance in regards to heat.

[t44tq]

t44tq, show us where the evil 996 kit touched you

Or better yet, f/o to some other thread. No one claimed the 996 kit is the best. This is a diy thread.

A lot of people are under the misconception that this will improve your heat capacity, which is not correct. Since you have no manners I’m not going to continue engaging with you, but as an information sharing exercise, I posted my thoughts.