Carbon ceramic brakes

[paulm]

Dear All,

As I approach that stage when my 996TT needs replacement brake discs (corrosion again!) I am thinking about fitting the SystemST carbon ceramic brakes which are lower cost than the Porsche ceramic discs

Has anyone fitted these or know anyone who has experience?

Many thanks

Paul

 

[marcus a]

if you want to save some cash.....
just a thought but the main dealers are offering a service to re-skim and re-drill -- far less than replacements!

 

[paulm]

Thanks - Good thought - guess it depends how bad the corrosion is.

I'm quite interested in the benefits of the ceramic brakes - light weight; no fade etc.

Cheers

Paul

 

[sawood12]

Why not look to some of the steel offerings from aftermarket producers such as Performance Friction or AP? Ceramic brakes have their downsides as well as upsides. The problem with ceramic is that is has very low Coefficient of Friction at low temps so they tend to have to get alot of heat in them before they are effective - clearly not good in a street car. Don't necessarily assume that Porsche are trying to rip you off for the sake of it with PCCB. One of the reasons the PCCB's are probably so expensive is because they will be an and exotic and expensive blend of mateirals to provide you with good braking performance when cold and hot. You might not be getting such a wide window of operiation with the aftermarket ceramic options that are probably primarily intended for racing where the cold performance is not so cruicial.

Also these ceramic composits are very fragile, again the PCCB's will have been blended to try to make them tougher (though they are still quite fragile from all accounts), and the aftermarket setup might be even more fragile than PCCB's. I think with a good disc/pad set up from Performance Friction you'd have to be one hell of a driver to be hitting their limits.

 

[andymac]

If I walked into my local OPC. How much would it cost to put the PCCB's on my 996TT?

 

[Rodney Naghar]

SystemSTs cost around £1600 per corner compared to PCCB disks at £3k per corner (although I hear replacements are a lot less). They are made of solid carbon cermaic AFAIK not just a thin layer of carbon ceramic as per PCCBs (around 0.5mm) so should have much better longevity, although I have heard they take around 1k miles to bed in.
I've heard of one guy's car who SystemST used as a guinea pig, but he sold his car shortly afterwards (a 996 GT2 I believe) so not much feedback was to be had.

 

[spyderman]

ORIGINAL: Rodney Naghar.
They are made of solid carbon cermaic AFAIK not just a thin layer of carbon ceramic as per PCCBs (around 0.5mm)... 

You sure PCCBs aren't solid carbon? How could they claim the 50% (?) weight saving if it was only a laminate?

I find it very odd to read suggestions to those wanting to seriously track PCCB-equipped 911s they should replace them with steel. Porsche promote them a race-developed and -engineered yet the mags suggest they're no good (911 & Porsche World recently).

 

[Rotorhead]

In recent weeks I've tried the carbon ceramics on the 997GT3 (long term), the AM DBS (one of the 007 cars) and the 430 Scuderia, and I actually prefer the pccbs.

True, there were some issues with the early generation pccbs, but the latest Gen 3s seem deliver on road and track, and have been used successfully in the Porsche Supercup series for three seasons.

The point to remember is that their successful application goes beyond the discs. Although Porsche have improved the construction and durability, they have also improved cooling, rear brake bias and pad specifications.

Hopefully prices will come down, although they will never be cheap. But even on a road car the benefits are notable - improved and consistant stopping performance, significant unsprung weight saving (contributing to improved handling and ride comfort), no corrosion, no brake dust, and longer life expectancy.

I think ceramics are definitely the future - particularly for high end performance cars, but the benefits could be even more noticeable on something like a Boxster/Cayman.

 

[Rodney Naghar]

ORIGINAL: spyderman

ORIGINAL: Rodney Naghar.
They are made of solid carbon cermaic AFAIK not just a thin layer of carbon ceramic as per PCCBs (around 0.5mm)...

You sure PCCBs aren't solid carbon? How could they claim the 50% (?) weight saving if it was only a laminate?

The 0.5mm layer I mentioned is the laminated friction surface that is bonded to the rest of the rotor - it is the layer with the carbon ceramic weave which is used/suitable for braking, once that layer has worn through the PCCBs belong in the bin. I'm not sure exactly what the rest of the PCCB rotor is made of, probably another weaker type of carbon/ceramic composite. The SystemST rotors aren't laminated, they have the same construction right through.

ORIGINAL: spyderman
I find it very odd to read suggestions to those wanting to seriously track PCCB-equipped 911s they should replace them with steel. Porsche promote them a race-developed and -engineered yet the mags suggest they're no good (911 & Porsche World recently).

Unfortunately the rotors are known to delaminate well within their quoted lifetimes (100k miles+) and hard track use tends to reduce their lives considerably (especially if they are not cooled down properly as the rotors suffer most due to excessive heat soaking).

As Oliver mentioned, there have been 3 generations of PCCBS, and they have improved with every iteration (better cooling, better 'weaves', longer fibres etc) so they tend to fail less often, but they do still fail (I saw a 997 GT2 in the summer with rotors that were near the end of their lives)

 

[pressing]

Rodney you've made a pretty concise post regarding the comparison to PCCB (manufactured by SGL Carbon, the same construction as for all OE fitment Ceramic Composite discs for Aston Martin, Audi, Bugatti, Ferrari, Lamborghini & Porsche) to those of Surface Transforms.

The two reasons for the laminated construction in the SGL Carbon rotor and manufacturing time and cost.

After around 15k miles on my Carrera GT and probably 20 track days the front rotors were in the first stages of 'Carbon Burn'. This is where the outer laminated friction surface has started to break away from the body of the disc itself. I've had various converations with SGL Carbon and they have confirmed the rotors are still absolutely fine to use, but the heat generated by prolonged track use has started the delamination process.

I had a set of cast iron rotors and bespoke bells manufactured by Brembo as a temporary solution. The impact on the CGT's handling and steering was huge and I knew I had to find a light weight disc solution without the inherent issues of the SGL Carbon rotors.

After lengthy discussions with Surface Transforms and Movit (who are the agent for System ST Brakes) I elected to have a set of rotors manufactured, with cross drilling that could be fitted to the existing SGL bells.

I've attached a couple of pictures of the rotors fitted to the car, I've not had a chance to bed them in yet but have no doubt of their ability to offer equal performance and weight benefits to the SGL Carbon solution, whilst offering hugely increased durability and strength. (I have however had a previous version of the System ST discs fitted without cross drilling, on bespoke bells and they performed superbly).

System ST were originally founded to offer a braking solution for the French TGV high speed train. They came up with a Ceramic Composite disc that offered not only massive weight reduction (allowing less brake discs per carriage) but also vastly outperformed the cast iron rotors in braking and destructive tests.

The fibre lengths and orientation in the System ST discs combined with the entire disc being constructed of a carbon ceramic friction material make the System ST discs the only option for long life. They have had a customer with a Mclaren SLR that ran his pads until the pad material had totally worn away and the backing plate material was rubbing on the disc surface. System ST were able to skim the discs to get them true and they were re-used.

If you need a contact at System ST please let me know.

http://i6.photobucket.com/albums/y211/993rsr/SGL2.jpg
http://i6.photobucket.com/albums/y211/993rsr/SGL1.jpg

 

[Rodney Naghar]

John,

Good post. I see they have started drilling the rotors now, I remember a year or so ago they mentioned it wasnt worth/prohibitively expensive to drill holes in them. I guess they've got a new version out. Do you know how much your disks weigh? Are they good from cold or do they need warming up before you get good bite out of them? Do they still require about 1k to bed in? Are they the same price?

 

[pressing]

Hi Rodney

The drilling on mine was done after the discs are produced, which did add cost but I wanted to retain the OE look and also have the benefits of the cross drilling. I'd have to check my records to confirm the cost.

As for weight the solid, i.e non-cross drilled ST rotors on the previous custom Movit hats were 5.10kg. I would expect the cross drilled discs (with slightly less mass) on the SGL carbon hats to be around 5.00kg, the same as the PCCB's.

The solid discs I previously had fitted took around 1000 miles to bed in, although I was running a very hard Movit pad. These discs have covered 20-30 miles and I'm running the OE Pagid for PCCB's and they are already starting to bed in (when the surface of the disc looks 'glassy' the discs have bedded in). You can see on the larger pictures the outer and inner edge of the disc looks shinier than the rest of the surface.

As for price as my latest cross drilled discs were exchanged for my previous solid discs I'm not sure on current cost. Probably best to talk to Guido at Movit on this subject.

Regards

John

 

[goldenboy]

just a point to rember, my previous turbo had non-ceramic brakes and worked well on or off the track, my new turbo with ceramic brakes works very well on track but not so good for daily driving because they don't warm up quickly.

I will go back to non-ceramic brakes on my next car.

 

[Rotorhead]

ORIGINAL: goldenboy

just a point to rember, my previous turbo had non-ceramic brakes and worked well on or off the track, my new turbo with ceramic brakes works very well on track but not so good for daily driving because they don't warm up quickly.

No problems with the pccbs, from cold, on GT3. Some people have said they lack 'feel', but in my experience the pccbs are more inspiring than steels under all conditions.