PCCB's (or any aftermarket brakes for that matter) don't make you stop any quicker...they only reduce fade after long hours on a roadcourse. They will also improve feel. But you'll stop just as quick with stock brakes as long as you aren't hitting their limits on a roadcourse.

Stopping distance is almost purely function of rubber on the ground (surface area and/or stickiness), and weight.

 

Yes and no... PCCB equipped cars have been shown to have shorter stopping distance than the stock steel counterparts in 4 or 6 piston applications. The ceramics offer much lighter unsprung weight and better initial bite, which translates into shorter stopping distances. In addition, the PCCB rotor at 355mm is also larger than the stock 996TT steel rotor at 330mm, and it offers two more pistons in a longer caliper which offers more swept area against the rotor... which should in turn offer more leverage against the rotor and ultimately more brake torque.

 

Hamann - Could you please show me a reference where they have been proven to provide shorter stopping distances on equal cars with equal tires?

It wouldn't make sense that they could, because as long as you have enough brake torque to lock up the wheels (or take them to the limit of lock up with ABS), then it becomes a function of traction only. And both the stock brakes (which are outstanding), as well as PCCBs, have the ability to lock the wheels up and/or take them to the point where ABS kicks in.

I do agree with you about the weight savings, and they also provide better fade-resistance and feel...but even Porsche won't claim that PCCB's shorten stopping distance (as quoted below). Only better/stickier tires can do that. Same reason why the Viper can outstop the C6 Z06. The Viper has better tires (larger rears and no run-flats).

http://www.porsche.com/usa/accessori...n36/n100/n116/

 

I too have the Gen 1 PCCB's in my 2003 X50 - nearly 130,000 miles of street and track driving and without question I swear by them - I feel they are far superior to the red's in both longevity, fade resistence and stopping distance (I do not have numbers to prove it and I previously owned a Turbo with the reds) but I know there are few if any cars out there on the track that can out stop me in an emergency - instructors who have been with me at the track have been amazed at how short the stopping distances are on the car when threshold braking on a long straight, in fact one instructor was actually laughing during one session at the Glen on the back straight - also this is on the stock Pirelli tires. I preface with saying I typically spend 3 or so laps in each heat progressively pushing the brakes and tires to generate heat in them - that seems to work best for the tire/brake setup in my car - also a good run after to cool them post session is important. FYI - I just looked into the old car folder and dug up some original literature from the factory on the Gen 1 PCCB's from page 6 - "As well as featuring six-piston monbloc calipers at the front of the car, PCCB uses an innovative new composite brake pad offering extremely high and consistent levels of friction under braking. The crucial benefit of compsite pads anad discs is that temperature is no longer a major factor in brake performance. Apart from reducing braking distances by some considerable margin - particularly under heavy use - PCCB offers much safer deceleration from high speed as well as maximum resistance to fading." My two cents. T2

 

While I have no doubt that your car feels like it stops faster (which is important in and of itself)...it just doesn't work like that. It's similar to the whole "butt-dyno" thing.

Were you to measure the stopping distance of another TT with standard brakes, that's the exact same weight as your car, with the same tires, and on the same track...it would stop in the same distance.

Have you ever noticed that you don't read about any Porsche's with PCCB's setting braking records in magazine reviews? It's because it never happens. The distances are always the same as the Porsches that are running the standard brakes.

Again, under heavy braking (like on a roadcourse), the PCCB's won't exhibit fade as much as the stockers...and will feel much better. But really, any good aftermarket BBK will do the exact same thing.

Walter Rohrl seems to agree. From Panorama magazine, June 2006, Page 43:


Here's more info:

http://forums.rennlist.com/rennforum...26&postcount=3

http://forums.rennlist.com/rennforum...82&postcount=3

 

Sorry this is off topic but why to people convert to brembo gtr's then?
Do these provide better stopping distance?

 

No. None of them provide better stopping distance. Stopping distance is almost entirely a function of tires/traction.

They convert to BBKs like GTR's for looks, better pedal feel, reduced weight, and resistance to fade. All GREAT reasons...but don't expect to stop in a shorter distance. The limiting factor is always going to be the tires and traction. You cannot outbrake your tires. Period.

Unless you heavily track your car, the stock brakes are outstanding in almost all situations.

 

Hmmm. Good to know. Thanks.

 

I'm with Divexx here. I don't think there is much difference between any of the brake combos on the first stop.

The PCCBs WILL stop faster in a hard use racetrack situation where steel calipers are heatsoaked and are starting to fade.

 

pccbs will not stop faster. it will accelerate quicker.

 

Leave it to OAK to summarize so succinctly. Scott has got it right. There is however an immeasuarble advantage to thinking you can stop faster at the track.

 

Scott, i'm totally with you on this one!

There is a big problem with the pccb's here in the UK, I know a few that are rippin' their hair out because they are fecked (the discs are) Those who have hit gravel traps with them discs are having major problems. I was talking with a regular track guy who tracks his GT3 nearly every week (also has the Turbo pccb's) and he reckons the discs are not worth a ****! He runs floating steels on his set up! I will try and dig out the posts on pccb's along with pictures, you will be shocked!

 

That's really interesting, Stevo. I'm looking forward to reading more about it. Thanks.

The really important thingthough is that Joe stopped in time regardless of what brakes he was using. Otherwise, that could have been one very bad OP.

 

Here is just one horror pccb link, check these out! If you can't see the pics let me know as I am reggy'd there and I can upload them here, I will find other posts later!

http://www.stuttgartnines.co.uk/uplo...Cspan%20style=

 

I think it's about time I created a PCCB thread on its own so we can stop threadjacking Joe's thread.