Porsche Brembo 996 BBK conversion

[repoman89]

There is a pretty big difference in how much fluid is moved, the pedal has noticeably more travel than my stock ZCP setup did and some simple math will confirm. Some might choose to swap in a larger master cylinder if there was a plug and play one available for firmer brakes. I find it acceptable, makes it easier to heel and toe actually being a little deeper in the brakes.

[Tbonem3]

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.

[Obioban]

If there was a big difference in how much fluid was moved, you'd have to change the master cylinder.
If there was a big difference in swept area, the 996 setup wouldn't work over ZCP rotors.
Brake pistons do not dissipate heat- they're actually ideally thermally insulated so that it's harder for heat to get into the fluid.
Losing pad material actually generates the friction needed for braking and creates heat, not the other way around.

You're not fully versed in how brakes work based on your post above. Rotor mass is the biggest factor- the rotor is a big heat sink, which is why you need to ventilate the rotor and bring cool air to the rotor to help the rotor dissipate heat from braking.

Those thin 28mm rotors can't absorb that much heat- there's a good reason why motorsports brake setups generally have a lot more mass- the Essex/AP kit runs 32mm thick rotors, for example.

I'm actually surprised how well my ZCP (with 996 calipers) rotors are holding up. They've already outlasted the stoptech 335/32s I ran once (though they're not yet anywhere near the life I got out of the Brembo 355/32s, yet). That said, I also don't care-- being free (FCP) means service life basically isn't a consideration. But, I've already gotten a full year of events out of them.

[t44tq]

Rotors have changed. Few m3s are zcp.

Base are 325x28mm, ZCP are 345x28mm. Bigger diameter, same thickness- you'll marginally increase heat capacity this way. You need to go thicker for great heat capacity. Thermal mass is the key.

[t44tq]

If there was a big difference in how much fluid was moved, you'd have to change the master cylinder.
If there was a big difference in swept area, the 996 setup wouldn't work over ZCP rotors.
Brake pistons do not dissipate heat- they're actually ideally thermally insulated so that it's harder for heat to get into the fluid.
Losing pad material actually generates the friction needed for braking and creates heat, not the other way around.

You're not fully versed in how brakes work based on your post above. Rotor mass is the biggest factor- the rotor is a big heat sink, which is why you need to ventilate the rotor and bring cool air to the rotor to help the rotor dissipate heat from braking.

Those thin 28mm rotors can't absorb that much heat- there's a good reason why motorsports brake setups generally have a lot more mass- the Essex/AP kit runs 32mm thick rotors, for example.

[Arith2]

Rotors have changed. Few m3s are zcp.

This applies to me.

The 996 Brembo setup discussed here is using OE BMW rotors- there is no improvement in heat capacity, as the rotors have not changed. There is a difference between the base rotors and the ZCP rotors, but if you already have the ZCP rotors, there is no difference.

Rotors are definitely not the only factor in heat dissipation. It is objectively false that ZCP brakes have the same heat capacity. When losing pad material, you lose heat. When losing rotor material, you lose heat. Pads matched with certain rotors will affect this. That's literally how rocket engine stop from melting. There are four pistons with a lot more brake fluid as well as more caliper surface area to dissipate heat. There is more fluid in the calipers for heat capacity. The pads will also be applied more evenly rather than more on one side which will utilize the rotor cooling much more effectively. There is also the fact that there less force is applied with the same pedal force allowing for more fine tuned braking. You have a wider range of tolerance. Don't skip leg day and the performance is there.

[Tbonem3]

Rotors have changed. Few m3s are zcp.

[t44tq]

Heat capacity, modulation/feel

If you're not going to be stopping hard repeatedly, you're better off with stock brakes.

The 996 Brembo setup discussed here is using OE BMW rotors- there is no improvement in heat capacity, as the rotors have not changed. There is a difference between the base rotors and the ZCP rotors, but if you already have the ZCP rotors, there is no difference.

[Arith2]

I really prefer the more rear bias braking from using the same pads. The Porsche OE Textars do alright. I've seen plenty of Porsches tracking them as well. There is a huge difference in the Textar brand and Porsche OE pads, contrary to popular belief. They don't grip as well and are glazed very easily. Get the Porsche ones because in this case, you get what you pay for.

Just an FYI for those not reading the entirety of the 34 pages, this swap will work with stocks 18s but ONLY with at least 12.5mm spacers. They can't be 12mm or they're touch. I did the math and measurements on the Brembo website about checking for rim clearance. My math turned out to be correct. I think I came to needing 11.9mm extra. I offset the rear with 10mm spacers just to balance out the width increase.

The calipers for the Carrera 4S are larger so don't get those. Also, 997 started in 2005 and 996 ended in 2006. 987 Cayman and Boxster S have the same part numbers on the calipers so those should be good post 2005. Be careful on what you order. Pelican couldn't send me the right pins and springs after a few tries. They kept sending Cayenne/997 ones. There is also an update in pins and springs which front pads for the 986 boxster actually changed. I grinded off the pins off the pads (wear a full faceshield) and they fit. One did hit my faceshield pretty hard so I was thankful to be wearing it over just safety glasses.

[heinzboehmer]

I absolutely LOVE how easy it is to do brake pad changes. Any time I do it at the track it makes people around me jealous.


Sent from my iPhone using Tapatalk

You're making me jealous

I've been passively looking for used calipers recently for exactly this reason. Yeah sure, all the other things would be nice, but what I really want is to be able to do pad changes with basically zero effort.

[DvSkD4]

I absolutely LOVE how easy it is to do brake pad changes. Any time I do it at the track it makes people around me jealous.


Sent from my iPhone using Tapatalk

[eljay]

What's the going rate for a set these days?

P.S. What a mistake clicking on this thread was!! It's gonna cost me.

[Thoglan]

Getting quite hard to source a set of these for a decent price. Especially in my area. Twice I thought I'd found a set for a good price before they disappeared/price changed before I could get them. Shipping them anywhere is pretty much prohibitively expensive as well given the weight of the calipers.

[Tbonem3]

No need to remove caliper to swap pads as long as you don't employ the damper inserts.

Weight loss is one of the best qualities of the kit. Looks is good too ofc, compared to stock.

[eljay]

Heat capacity, modulation/feel

If you're not going to be stopping hard repeatedly, you're better off with stock brakes.

Got it! Thank you.
They do look good though and from what I've read, the front/rear bias remains very close to stock ZCP.
Is there any info on weight differences of 996 calipers with brackets vs stock?

edit:
I think another benefit worth mentioning that I can see with the 996 calipers is how easily the pads can be changed. No need to remove the caliper, correct?