Defer to John but I'd guess hard no. 3.12 are very very abrasive and can wear steel fast if not warm.

 

First off, thank you for the kind words re product presentation.

Covering the pad question first - Ferodo 3.12 will be too abrasive for a SiC-dominant CCB surface. I strongly recommend either my pads or something specifically designed for an adhesion based friction regime (e.g. Pagid RSC / Endless W007/008).

As to your question about sizing, you’re thinking about the right variables (thermal headroom + pad temps), but one key point: the smaller rotors don’t do more work in the physics sense. For a given stop from a given speed, the energy that has to be absorbed is basically set by vehicle mass + speed (kinetic energy). Same 3200 lb car, same speed, same tires, both pushed to ABS = roughly the same total energy that gets turned into heat. Rotor diameter changes how that heat shows up:

• Smaller diameter = less torque leverage, so you generally need more line pressure / clamp force to hit the same wheel torque.
• Smaller rotor also usually means less thermal mass and less swept area, so peak temps rise faster in repeated high-power stops. That’s what can accelerate pad wear (and increase the chance of pad material getting unhappy).

Practical reality:

• Street + spirited driving: both setups are traction-limited long before they’re heat-limited, so longevity differences are modest.
• Repeated high-speed track braking: 380/380 will generally run cooler and be easier on pads over a long day, all else equal.

On the field case point, ironically some of my current most 'abused' field setups are smaller. I have many people tracking on 305/292 Alfa 4C setups and extensive track testing is ongoing with 338/282 S2000 setups. I have people tracking 3800-4300 lb BMWs on 380/370. There will be no shortage of data on smaller sizes.

For the 718 GTS 4.0 specifically, 350/330 is more than sufficient for street use and occasional light track days. If someone is tracking extensively and wants maximum thermal headroom, I’d steer them toward a larger setup (typically 380/350), which a few owners have already elected to run. Either way, we’ll have solid data across all of these configurations as things progress

Exciting times in the world of CCBs, in my opinion.

 

A very good first day at the track with my BSPK 410/390 setup. Took it easy the first couple of sessions to brake everything in (pun intended), get a good transfer layer of pad material onto the rotors, and put everything through a couple of serious heat cycles . Then full send for the third and fourth sessions with a friend in a decked out 992 GT3. We had a blast running nose to tail occasionally swapping positions. The brakes performed beyond my expectations and I will give further details later tonight.

 

I'm planning to do the same and move from OEM steel and 3.12 front 1.11 rear to BSPK and their track pads

 

I’m really looking forward to trying these new brakes out on track even more than I normally do after other tweaks I’ve done to date.
Tyres will be next as I’ve had enough of the Cup 2s

 

After putting the BSPK carbon rotors on my car I went for a typical bedding in drive with at least a couple dozen smooth stops from between 60 to 80 mph. I did decide on some RSL-29 pads for the track which are notorious for a longer break in process. More squealing during that process than expected but not surprised. I suspect John's ceramic pads will be better here. On the drive today to the track, no noise, and no noise anytime at the track today. I took it easy the first two sessions and watched the rotors accept more and more pad material and get that bluish hue to them. Just like steels will do. Nice to have the lighter color to these rotors and be able to see that.



The most immediate effects noted on my first two break in sessions was the cars willingness to turn in, the obvious lightness of the wheels over the curbs, and the increase in transient acceleration upon applying throttle. The willingness to turn was noted especially on corner entry but also during mid and late corner requests for more steering angle. This was by far more noticeable than I had expected, but of course a much welcomed improvement in the cars handling characteristics. The increased smoothness over the bumps and better acceleration were expected and certainly noticeable, which made the car even more fun to drive. Less mass in the rotors significantly reduces gyroscopic procession and allows for these noted improvements. If you have ever held a gyroscope, the faster it is spinning or the bigger it is, the harder it is to move it around. It tends to stabilize things and make it harder for changes in movement to occur. By reducing rotational weight with the carbon rotors, we are reducing the moment of inertia for the car's spinning wheels to change direction. Therefore when you turn the steering wheel, go over a bump, apply the gas, and or hit the brakes; everything happens more easily with less resistance to change in direction. Dumping ~35 pounds off of the 4RS's brakes definitely made a huge difference for me on track today. Maybe not as noticeable on the road, but the car did feel lighter on its feet while driving on the street.

How was the braking? Well the 4RS has amazing brakes to begin with, so thankfully that pretty much stayed the same. During the third and fourth sessions with my friend in the 992 GT3, we just let rip. The brakes were excellent with consistent stopping power and good modulation characteristics. Maybe a bit more thermally stable near the end of a session than steels but very comparable overall. I know some people think after listening to the media that carbon rotors stop the car better than steels, but that is really determined by the tires grip. Once you get up to the quality of brakes that Porsche puts on its GT cars, it is pretty much parody here. I believe it is more in the sensation of the carbons being a bit firmer with the pad pushing up against a rock solid rotor surface versus the steels which are a bit more linear but with a bit of a compressible feeling to them especially when hot. No fading with either, but maybe a little more consistent pedal pressure to achieve the same braking torque throughout the session with the carbons vs steels. Bottom line, the braking is excellent with these rotors.

My friend said he could not brake as late as me and was driving the wheels off his GT3 to keep. Both cars have been modified and are maintained by the same mechanic. Definitely apples to oranges here, but the end result is basically the same. We were the two fastest cars on the track today driving together and having a blast. When we come up on slower traffic, they see us coming up fast in tight formation and usually let us both by at the same time together even in some tighter places. Some other threads here like to compare these two cars and try to declare a winner, but when each is set up properly, they are very comparable while on track driven by similarly skilled drivers. Porsche chose to take the refinement of the GT4 RS only so far. Bottom line to me is that we can take what has been learned here over the last few years and make those additional improvements ourselves that Porsche left on the table.

So needless to say. I am very happy with the BSPK carbon rotors and feel that they have exceeded my expectations. It has been fun to work with John and introduce this prototype set to the Porsche market. Again, I am not affiliated with BSPK in any way, and I did pay for my rotors. For those of you that know me here, I call it like I see it, and have not been asked or swayed to provide a positive comments here. This is just another product that I really like and has helped lift my GT4 RS to an even higher level of performance. I will keep posting as time goes by about the rotors and especially the various pads that I will try here in the near future. Good luck to everyone planning to get a set of these rotors.

 

As always, thank you for sharing your experience and being the mod "ice breaker"

Did you change the config on PIWIS and set the brakes to carbon ?

 

RSL 29's on CC rotors? I thought they were for steels.

 

RSC line is usually the Pagid range to be used on CCM rotors, but you can use RSL29 on some CCM rotors, but they are aggressive.
So you definitely should not use them on PCCB.

 

Awesome write-up! Thank you!

 

I have asked around about this and I understand that this might be a bit of an internet myth… although I’m happy to corrected :

There is a flag for steel or pccb brakes in PIWIS, but apparently it does not effect any change to braking behaviour, instead it is just an option selection for the car configuration record so that if parts need to be ordered for the car, you’d get steel or PCCB parts - think pads, bolts etc.
There arent any additional or differential parameters for the ABS controller… which kinda makes sense else we’d need to be tuning this if we changed pads or went to stickier tyres and we don't do this.

 

@lovetoturn thank you for the detailed first impressions. I am looking forward to getting my set installed later this spring.

 

This is just based on the feedback from a number of local guys using them on track with GT3s and 4Rs's on their PCCBs. I know, not really what you want to do, but they are having favorable results, at least until they get the bill to replace their rotors. The RSC1's just aren't strong enough for serious track usage and the RSC2s are hard to get. So I tried something a little different to common convention to start out with. I would not recommend the RSL-29s yet to anyone as they are yes a bit aggressive on the rotors. Planning on trying out John's track pads next, and then maybe Endless W007s but the are $$$. I suspect that the RSC2s are similar to the endurance nature of the RSL-29s, but a less aggressive formula designed for the carbon rotor.

These other pads are all over $1k per set, so getting your first pads from John included in the price with the rotors makes it even more of an amazing deal.

 

Got it thanks 👍

 

Thank you for clarifying that TDT. My mechanic said it was bit more complicated now to make such a change in PIWIS and wasn't sure it would make much of any difference. That is part of why we stuck with the OEM sizing for the carbon rotors and used the 390 size. If all other parameters are the same, then a slightly larger rear disc will only transfer something around 1% more braking to the rear of the car. This will slightly stabilize the rear of the car while trail braking, which I find a good thing for our cars to help calm down the rear end of the car. It is plenty easy to trail brake and rotate into the corner.