View Poll Results: Did you order PCCBs on your GT3/RS?
Yes
82
56.94%
No
50
34.72%
Undecided
12
8.33%
Voters: 144. You may not vote on this poll
PCCBs. Not a rehash.
12-06-2006, 11:53 PM
#32
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With all the arguments for and against the ceramic brakes I am wondering if anyone has considered installing the Brembo GTR brakes. They are supposed to be almost as light as the ceramics and offer equal performance and more durability. They run about 13K.
I remember another thread were it was suggested that one could sell the original brakes in the car( presumably in almost new condition) and get about 3-4 thousand dollars. This amount could then be used towards purchasing the GTR kit and make it almost the same as the price of the ceramics. Has anyone done this? Would you consider this option?
I remember another thread were it was suggested that one could sell the original brakes in the car( presumably in almost new condition) and get about 3-4 thousand dollars. This amount could then be used towards purchasing the GTR kit and make it almost the same as the price of the ceramics. Has anyone done this? Would you consider this option?
12-07-2006, 01:19 AM
#34
I ordered the ceramics. I loved them on the Stradale. They were "grabby" around town but great on the track. The following statement may brand me a poseur, but I really loved the fact that there was almost no brake dust. Do the PCCB's make much dust? I'm not that fastidious about washing my cars and I find it annoying that the first time I drive the turbo (with iron rotors) after a wash, the wheels are coverd with brake dust.
12-10-2006, 01:37 AM
#36
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You can inspect your rotors every 3 track days and keep tracking on the surface porosity. When I inspected BobbyC's front rotors, there was noticeable porosity, the rear ones were smooth as glass. My front rotors (Gen I) show more porosity than BobbyC's car, my rear ones are smooth as new.
The way these PCCB rotors wear-out is by getting rough on the surface, to a point where they will just eat the brake pads. At that point you need new rotors. Once they get a high degree of porosity, they start to fall apart in chunks.
I switched from steel to PCCB to get real life feedback. I've a successful application running Pagid RS19, and Motul RBF 600/Castrol SRF.
The brake fluid will not extend the life of PCCB rotors, a higher dry/wet boiling point for the brake fluid just increases the threshold for a soft brake pedal.
A few things with impact on PCCB rotors life expectancy:
1) When braking, if the driver invokes the ABS, the brake pads will be hammering the rotors, causing damage to the surface.
2) Sticky tires increase the stress on the brakes. Slicks --> DOT-R --> Full street tires.
3) Driving skills and style have a lot to do with brake usage. Typically, novice drivers use too much brakes. There are plenty of intermediate drivers running 20-30 secs behind the car's potential pace per lap, those drivers get longer lasting brakes. I've been able to keep the pace of a PCA White group at LRP, leaving the car in 3rd gear and not using the brakes at all. The harder and longer you use the brakes, the sooner they will need replacement.
4) Inspect the brake pads. Brake pads crack with track usage, a brake pad with a high level of cracks becomes a really abrasive sandpaper, and it will damage the rotors.
On Christophorus, they mentioned the PCCB last 10x longer than steel rotors. Porsche SuperCup Teams can run almost a full season with one set of PCCB, they claimed. This is just typical Porsche marketing.
In fact, the Porsche SuperCup is just a dozen of Sprint races per year, that last 25-30 minutes each. That's 12 track sessions of 30 minutes, plus qualifying and practice. Qualifying is a 45 minutes session, typically on Saturday, and practice is just a 30 minutes session, typically on Friday. We have around 105 minutes (less than 2 hours) of track time per SuperCup race, that's about the same we get per track day at DE. Let's round to two hours per race weekend, and assume the PCCB last the entire season, still after 24 hours of hard diving the PCCB will need replacement. I bet each SuperCup team runs fresh brake pads and brake fluid at every race.
If they're replacing front rotors every ten races (the possible reason for Christophorus 10x comment), that's 18 hours of race life for front rotors.
If I was to buy another Porsche, I would get PCCB. But I will keep using metal rotors for DE, and PCCB for Time Trials, AutoX and street driving.
The 997 GT3 380mm/350mm metal rotors might be available already. They might be a direct swap with the US 997 GT3 Cup rotors. I'm running rear 997 GT3 Cup rotors on my PCCB 996 GT3 (350mm), and I won't be surprised if Porsche is re-using the 996 GT3 PCCB rear brakes setup on the 997 GT3.
Don't expect PCCB to last forever, and keep that $10k bill in mind. Of course, you can always coast around the track 30 seconds slower than a fast lap, and claim you have 50 track days on PCCB without problems, in such case I can run a set of steel rotors that will never crack either.
The way these PCCB rotors wear-out is by getting rough on the surface, to a point where they will just eat the brake pads. At that point you need new rotors. Once they get a high degree of porosity, they start to fall apart in chunks.
I switched from steel to PCCB to get real life feedback. I've a successful application running Pagid RS19, and Motul RBF 600/Castrol SRF.
The brake fluid will not extend the life of PCCB rotors, a higher dry/wet boiling point for the brake fluid just increases the threshold for a soft brake pedal.
A few things with impact on PCCB rotors life expectancy:
1) When braking, if the driver invokes the ABS, the brake pads will be hammering the rotors, causing damage to the surface.
2) Sticky tires increase the stress on the brakes. Slicks --> DOT-R --> Full street tires.
3) Driving skills and style have a lot to do with brake usage. Typically, novice drivers use too much brakes. There are plenty of intermediate drivers running 20-30 secs behind the car's potential pace per lap, those drivers get longer lasting brakes. I've been able to keep the pace of a PCA White group at LRP, leaving the car in 3rd gear and not using the brakes at all. The harder and longer you use the brakes, the sooner they will need replacement.
4) Inspect the brake pads. Brake pads crack with track usage, a brake pad with a high level of cracks becomes a really abrasive sandpaper, and it will damage the rotors.
On Christophorus, they mentioned the PCCB last 10x longer than steel rotors. Porsche SuperCup Teams can run almost a full season with one set of PCCB, they claimed. This is just typical Porsche marketing.
In fact, the Porsche SuperCup is just a dozen of Sprint races per year, that last 25-30 minutes each. That's 12 track sessions of 30 minutes, plus qualifying and practice. Qualifying is a 45 minutes session, typically on Saturday, and practice is just a 30 minutes session, typically on Friday. We have around 105 minutes (less than 2 hours) of track time per SuperCup race, that's about the same we get per track day at DE. Let's round to two hours per race weekend, and assume the PCCB last the entire season, still after 24 hours of hard diving the PCCB will need replacement. I bet each SuperCup team runs fresh brake pads and brake fluid at every race.
If they're replacing front rotors every ten races (the possible reason for Christophorus 10x comment), that's 18 hours of race life for front rotors.
If I was to buy another Porsche, I would get PCCB. But I will keep using metal rotors for DE, and PCCB for Time Trials, AutoX and street driving.
The 997 GT3 380mm/350mm metal rotors might be available already. They might be a direct swap with the US 997 GT3 Cup rotors. I'm running rear 997 GT3 Cup rotors on my PCCB 996 GT3 (350mm), and I won't be surprised if Porsche is re-using the 996 GT3 PCCB rear brakes setup on the 997 GT3.
Don't expect PCCB to last forever, and keep that $10k bill in mind. Of course, you can always coast around the track 30 seconds slower than a fast lap, and claim you have 50 track days on PCCB without problems, in such case I can run a set of steel rotors that will never crack either.
12-10-2006, 12:21 PM
#37
Excellent report -- thanks much. I was on the fence re PCCBs, but recently switched my RS order to include them. You indicate that if you were to buy another Porsche you would include them -- curious to get your detailed thoughts as to why.
12-10-2006, 12:33 PM
#38
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Just some additional info:
----------------------------
More information on the material:
http://www.sglcarbon.com/sgl_t/indus...sigrasic_e.pdf
--------------------------------------------------------------------------------
From the Christophorus #311 Article....
At the core of a state-of-the-art automotive brake is a disk. In the Porsche Ceramic Composite Brake (PCCB), this brake disk is exceptionally rugged and effective. Now the second generation has been rolled out.
Donatus Neudeck, manager of the Department of Brakes, Hydraulics and Actuation Systems at the Porsche Development Center in Weissach, is pleased with recent advances in deceleration. "Since 2001, we've been producing the ceramic brake on a fairly large scale. And thanks to our rigorous development program, we're already selling the second generation," he reports proudly. When it comes to brakes, making what's already excellent even better is often a matter of incremental advances. Accordingly, the specification for the Porsche Ceramic Composite Brake (PCCB) included just three objectives: improved cooling, reduced wear, and increased dimensional stability of the disk.
So what's actually new in the new-generation brake? To illustrate, Neudeck places two 350-millimeter-diameter brake disks side by side on his desk-one old, one new. That almost settles the issue right then and there. While the 20 air outlets in the first generation are oblong, the new ones are square. And there are twice as many outlets now as before. The perforation pattern on the braking surface has been changed as well. It used to be regular. Not it's more random. Neudeck explains that the reason is on the inside as he retrieves two cut-away models from a cabinet. While the cooling channels in the first generation follow an involute curve, the new channels are based on an Arcus design. This is an entirely new cooling channel geometry. It allows the cooling air to enter with a minimum of friction and accelerates it to a high speed as it exits. The brake disk becomes a turbine- to maximize airflow at any engine speed. At 200 km/h, an air flow of about 250 liters per second is conducted efficiently through these channels along the internal surface of the disk. The result: The new design has improved efficiency by 20 percent.
Now Neudeck rearranges the "show-and-tell" on his desk. He shoves the two cut-away models aside and puts a complete brake disk in their place. Then he wipes some grime off his hands with his handkerchief. "This disk was installed in one of our test vehicles and has traveled a total distance of 300,000 kilometers (186,300 miles)." Any visible wear? None. This disk, which had been mounted on the front axle, is still 34 millimeters thick, just like when it was new. "This disk doesn't really look so out of the ordinary. But then, it wasn't supposed to."
Abrasion resistance has been further improved. "We're using thicker carbon fibers now," notes Neudeck. Actually, they're fiber bundles. Three thousand fibers were previously used to form such a bundle; the new generation has 400,000! A company located near Augsburg has proven an effective partner in manufacturing PCCB disks. As a first step, carbon fibers are produced from the plastic polyacrylonitrite (PAN). These fibers are then heated and carbonized in a two-phase process-first in an oxidizing atmosphere, then with the air excluded. Then the carbon fibers are ground up and saturated in a synthetic resin to produce a sticky putty that can be shaped.
In the new brake disk, each carbon fiber bundle consists of 400,000 fibers (compared to 3000 in prior models).
"To create the new shape of the cooling channels, we use a 'lost core' that burns up without leaving a residue," Neudeck explains. The polymer components are allowed to harden in a heated press. The intermediate result is a carbon-fiber reinforced blank. The blank is heated to nearly 1000 degrees Celsius (1830 degrees Fahrenheit) in a nitrogen-rich atmosphere to convert it into pure carbon. In the next step, the disk is heated to about 1420 Grad Celsius (2590 degrees Fahrenheit) and infiltrated with silicon. The disk absorbs the molten silicon like a sponge. When the disk cools, silicon carbide forms, which is almost as hard as diamond. "The new fiber technology causes even more silicon carbide to form on the surface, which results in even greater resistance to wear and abrasion," Neudeck explains.
The "lost-core" process can be used to create more complex geometries than had been possible with previous production processes, which used to create two half-disks that were then joined and bonded together before being siliconized. At the same time, the new process can accommodate larger production quantities. In the future, the PCCB will therefore be available not only in the Carrera GT and the Turbo, but also in both models of the 911 Carrera and in the Boxster S.
The PCCB has reduced the weight of the braking system for the new 911 by 14 kilograms (31Ibs.).
Though Neudeck's team has just completed developing the second generation PCCB, its members are eagerly looking forward to further developments. "Since this is still a relatively new subject, we're learning by leaps and bounds," notes the team leader. One improvement they've achieved is the lower weight. In the new 911 Carrera, the brake disks weigh only half of what they used to weigh, and the complete braking system weighs 14 kilograms (3.1lbs.) less. "Lightweight materials-mostly aluminum alloys-are being used throughout the chassis," notes Neudeck. But not one of those engineering improvements has trimmed off as much weight as have the lightweight but rugged brake disks. According to Neudeck, the reduction in unsprung mass of the ceramic brake not only provides a more comfortable ride, but also improves driving dynamics. And in a Porsche, that's certainly an important advantage.
Before removing the demo disks from his desk, Neubeck delivers his final point: "Today the ceramic brake is still a high-end component. But it's technically so superior that we're working hard to make it available for more general use."
----------------------------
More information on the material:
http://www.sglcarbon.com/sgl_t/indus...sigrasic_e.pdf
--------------------------------------------------------------------------------
From the Christophorus #311 Article....
At the core of a state-of-the-art automotive brake is a disk. In the Porsche Ceramic Composite Brake (PCCB), this brake disk is exceptionally rugged and effective. Now the second generation has been rolled out.
Donatus Neudeck, manager of the Department of Brakes, Hydraulics and Actuation Systems at the Porsche Development Center in Weissach, is pleased with recent advances in deceleration. "Since 2001, we've been producing the ceramic brake on a fairly large scale. And thanks to our rigorous development program, we're already selling the second generation," he reports proudly. When it comes to brakes, making what's already excellent even better is often a matter of incremental advances. Accordingly, the specification for the Porsche Ceramic Composite Brake (PCCB) included just three objectives: improved cooling, reduced wear, and increased dimensional stability of the disk.
So what's actually new in the new-generation brake? To illustrate, Neudeck places two 350-millimeter-diameter brake disks side by side on his desk-one old, one new. That almost settles the issue right then and there. While the 20 air outlets in the first generation are oblong, the new ones are square. And there are twice as many outlets now as before. The perforation pattern on the braking surface has been changed as well. It used to be regular. Not it's more random. Neudeck explains that the reason is on the inside as he retrieves two cut-away models from a cabinet. While the cooling channels in the first generation follow an involute curve, the new channels are based on an Arcus design. This is an entirely new cooling channel geometry. It allows the cooling air to enter with a minimum of friction and accelerates it to a high speed as it exits. The brake disk becomes a turbine- to maximize airflow at any engine speed. At 200 km/h, an air flow of about 250 liters per second is conducted efficiently through these channels along the internal surface of the disk. The result: The new design has improved efficiency by 20 percent.
Now Neudeck rearranges the "show-and-tell" on his desk. He shoves the two cut-away models aside and puts a complete brake disk in their place. Then he wipes some grime off his hands with his handkerchief. "This disk was installed in one of our test vehicles and has traveled a total distance of 300,000 kilometers (186,300 miles)." Any visible wear? None. This disk, which had been mounted on the front axle, is still 34 millimeters thick, just like when it was new. "This disk doesn't really look so out of the ordinary. But then, it wasn't supposed to."
Abrasion resistance has been further improved. "We're using thicker carbon fibers now," notes Neudeck. Actually, they're fiber bundles. Three thousand fibers were previously used to form such a bundle; the new generation has 400,000! A company located near Augsburg has proven an effective partner in manufacturing PCCB disks. As a first step, carbon fibers are produced from the plastic polyacrylonitrite (PAN). These fibers are then heated and carbonized in a two-phase process-first in an oxidizing atmosphere, then with the air excluded. Then the carbon fibers are ground up and saturated in a synthetic resin to produce a sticky putty that can be shaped.
In the new brake disk, each carbon fiber bundle consists of 400,000 fibers (compared to 3000 in prior models).
"To create the new shape of the cooling channels, we use a 'lost core' that burns up without leaving a residue," Neudeck explains. The polymer components are allowed to harden in a heated press. The intermediate result is a carbon-fiber reinforced blank. The blank is heated to nearly 1000 degrees Celsius (1830 degrees Fahrenheit) in a nitrogen-rich atmosphere to convert it into pure carbon. In the next step, the disk is heated to about 1420 Grad Celsius (2590 degrees Fahrenheit) and infiltrated with silicon. The disk absorbs the molten silicon like a sponge. When the disk cools, silicon carbide forms, which is almost as hard as diamond. "The new fiber technology causes even more silicon carbide to form on the surface, which results in even greater resistance to wear and abrasion," Neudeck explains.
The "lost-core" process can be used to create more complex geometries than had been possible with previous production processes, which used to create two half-disks that were then joined and bonded together before being siliconized. At the same time, the new process can accommodate larger production quantities. In the future, the PCCB will therefore be available not only in the Carrera GT and the Turbo, but also in both models of the 911 Carrera and in the Boxster S.
The PCCB has reduced the weight of the braking system for the new 911 by 14 kilograms (31Ibs.).
Though Neudeck's team has just completed developing the second generation PCCB, its members are eagerly looking forward to further developments. "Since this is still a relatively new subject, we're learning by leaps and bounds," notes the team leader. One improvement they've achieved is the lower weight. In the new 911 Carrera, the brake disks weigh only half of what they used to weigh, and the complete braking system weighs 14 kilograms (3.1lbs.) less. "Lightweight materials-mostly aluminum alloys-are being used throughout the chassis," notes Neudeck. But not one of those engineering improvements has trimmed off as much weight as have the lightweight but rugged brake disks. According to Neudeck, the reduction in unsprung mass of the ceramic brake not only provides a more comfortable ride, but also improves driving dynamics. And in a Porsche, that's certainly an important advantage.
Before removing the demo disks from his desk, Neubeck delivers his final point: "Today the ceramic brake is still a high-end component. But it's technically so superior that we're working hard to make it available for more general use."
12-10-2006, 09:56 PM
#39
The Rebel
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Originally Posted by NJ-GT
...If I was to buy another Porsche, I would get PCCB. But I will keep using metal rotors for DE, and PCCB for Time Trials, AutoX and street driving...
12-11-2006, 01:16 AM
#40
Yet more info re PCCBs: the PCCBs were developed by Porsche with the assistance of a third-party, SGL Brakes. Here is a link to their website:
www.sglcarbon.com/sgl_t/brakedisc/index.html
www.sglcarbon.com/sgl_t/brakedisc/index.html
12-13-2006, 11:16 AM
#44
Three Wheelin'
Originally Posted by RR
I originally specced PCCB's then changed back to steel rotors.
Getting engaged, it was PCCB's or diamond ring.
Getting engaged, it was PCCB's or diamond ring.
12-13-2006, 11:31 AM
#45
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Originally Posted by frayed
You know, i have pccbs on order and am still waffling. Diam!
Jeff, an enclosed Pace 20" trailer is only $7500. Would probably get alot more usage out of that with your growing fleet of track bling. BTW Rob says the 360 is at FOH. I guess the GT3 bug became a terminal infection?