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Discussion Starter #1 (Edited)
I think both parts are supposed to be significantly lighter than the parts they replace, but I'm not sure by how much. I know that they're pricey, and it would be foolish to buy either just for the weight savings, but I'm still curious. And I assume the listed 2,955-lb curb weight is with the base brakes and sport seats?

... I ask in part because I feel like the carbon brakes are going to be very hard to justify on this car given that 15" rotors on a ~2900-lb car with only 385-hp already seems quite a bit more than adequate. It's hard to imagine those brakes ever fading even on high speed tracks. Circuit of the Americas is the most aggressive one around here, but I bet the base brakes could survive even that with the right pads/fluid... Weight savings, and the extended rotor life are always nice, though.
 

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Discussion Starter #2
I just saw the "what do you want to know..." thread, so apologies if this is the wrong place for me to be asking this question. I will ask in there, too, just in case. I'm still not sure, though, so I'll let a mod lock this thread if it shouldn't be here.
 

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If you are a track rat they won't last so long but they will last maybe 5-10 times longer than stock brakes.
No so. Carbon ceramic brakes will last practically forever if they never get hotter than a certain point - a point that is invariably exceeded during track use. Some reports that iron brakes will actually last longer than PCCBs with heavy track usage. Given the replacement costs (currently $20K for all four corners), the cost per track mile is purportedly around $10, more than four times that of iron brakes.
 

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No so. Carbon ceramic brakes will last practically forever if they never get hotter than a certain point - a point that is invariably exceeded during track use. Some reports that iron brakes will actually last longer than PCCBs with heavy track usage. Given the replacement costs (currently $20K for all four corners), the cost per track mile is purportedly around $10, more than four times that of iron brakes.
This is not the experience of my friends who have PCCBs on their GT3s. Most are reporting very long brake component life while hitting 20 track days/yr. only a few data points but top drivers turning very fast laps.
 

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This is not the experience of my friends who have PCCBs on their GT3s. Most are reporting very long brake component life while hitting 20 track days/yr. only a few data points but top drivers turning very fast laps.
I'm going by the information posted in this thread. I was wrong about the calculated cost per track mile for PCCBs - it's actually over $26. Part of the issue is that Porsche overcharges egregiously for replacement rotors (similar disks made by the same manufacturer for GM retail for $5K for a full set). Regardless of which reports are more accurate, I'm not taking a chance on PCCBs, given the heavy track usage I plan for my GT4.
 

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Yep that thread massages 1data point to the nth speculative degree. It's not consistent with 1/2 dozen drivers in SoCal that have been running the same PCCB brake hardware for 4- 5 years.

i run steel rotors and there is nothing wrong with that choice. they work great and I get 20 track days on Zimmerman fronts in the advanced TimeTrial group. PCCBs are still a viable choice internet rumors notwithstanding.
 

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I was looking at PCCBs for my Spyder (keyword = looking, I enjoy the homework). Based on the cost and presumably little braking performance gain per people on the forum and some of the pros, I cannot see making the jump (at least as of now, ask me again in 5 minutes). The things that still call to me on paper are the perceived hp gain (I have read 20-40 so I will assume it is in the middle) and the unsprung weight loss increasing chassis responsiveness. However, I am probably dreaming that I will ever need or realize either of these gains as a street driver. The durability as a street driver is also nice.

what I do not like is that the Spyder already has upgraded brakes but there is no cost difference between PCCBs on an S or the Spyder. The GT4 PCCBs are huge, but again they cost the same as an upgrade on the Spyder to a much smaller disk. So I feel like a Spyder owner isn't getting a fair deal from a value for money perspective.

The the nail in the coffin is that the yellow calipers won't match my GT Silver / red interior motif!!! Lol
 

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I was looking at PCCBs for my Spyder (keyword = looking, I enjoy the homework). Based on the cost and presumably little braking performance gain per people on the forum and some of the pros, I cannot see making the jump (at least as of now, ask me again in 5 minutes). The things that still call to me on paper are the perceived hp gain (I have read 20-40 so I will assume it is in the middle) and the unsprung weight loss increasing chassis responsiveness. However, I am probably dreaming that I will ever need or realize either of these gains as a street driver. The durability as a street driver is also nice.

what I do not like is that the Spyder already has upgraded brakes but there is no cost difference between PCCBs on an S or the Spyder. The GT4 PCCBs are huge, but again they cost the same as an upgrade on the Spyder to a much smaller disk. So I feel like a Spyder owner isn't getting a fair deal from a value for money perspective.

The the nail in the coffin is that the yellow calipers won't match my GT Silver / red interior motif!!! Lol
Agree with all above. The advantage of PCCBs for most of us is the decrease in brake dust. The lower unsprung weight and mildly improved stopping power - most of us wont even notice. The yellow calipers don't look good at all IMHO unless you have a racing yellow car. My steel brakes are awesome. The stopping power limit is really the tires, not the brakes anyway.
 
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Discussion Starter #11 (Edited)
The things that still call to me on paper are the perceived hp gain (I have read 20-40 so I will assume it is in the middle)
I think the people making these claims are way, way off. I'd like to see some math or data for how they came to that figure. Personally (admittedly, anecdotally), I have some experience that says it won't be anywhere near that much of a perceived gain.

On my last car, I bought aftermarket rims that were about 6.5 lbs lighter at each corner up front and 8 lbs in the rear than the factory wheels. It was certainly a noticeable difference, but not necessarily in a very good way... I found my tires spinning much more easily after the swap, presumably as a result of the significantly decreased rotational inertia. While the MOI was lower, the car's overall weight was not significantly lower. So the wheels wanted so spin faster than they were physically capable of moving the car forward. And unlike when you add more power, this is not a problem you can fix by simply getting stickier tires (because if you stop the spinning with stickier tires, you also eliminate most of the rotational inertia improvements). So my acceleration did not improve much.

Still, any weight savings are nice, and unsprung weight is even better. But honestly I think people saying they "feel" a 6-10% increase in power are off their rocker, and I really doubt there is any data to back that claim up.


Agree with all above. The advantage of PCCBs for most of us is the decrease in brake dust. The lower unsprung weight and mildly improved stopping power - most of us wont even notice. The yellow calipers don't look good at all IMHO unless you have a racing yellow car. My steel brakes are awesome. The stopping power limit is really the tires, not the brakes anyway.
I don't think stopping power will improve at all except for maybe a slightly more "grabby" feel since the rotors will be larger. But stopping distance should be nearly identical, and advantages on the track should be minimal, at best, since I doubt those massive steels will fade at all on a ~2900-lb car.
 

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Real demonstrated benefits of PCCBs:
- lower unsprung weight
- lower rotating mass
- longer life
- better heat management in continuous lapping
- less dust??

nonsense internet chatter :
- more horsepower. :hilarious:
- shorter stopping distance
http://hpwizard.com/rotational-inertia.html#answers

disadvantages:
-cost of components

folks often make stuff up to support the choices they have made and that "stuff" gets passed around pretty quickly.
 

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Discussion Starter #13
Real demonstrated benefits of PCCBs:
- lower unsprung weight
- lower rotating mass
- longer life
- better heat management in continuous lapping
- less dust??

nonsense internet chatter :
- more horsepower. :hilarious:
- shorter stopping distance
The Effects of Rotational Inertia on Automotive Acceleration

disadvantages:
-cost of components

folks often make stuff up to support the choices they have made and that "stuff" gets passed around pretty quickly.
Agree, but one thing I'd add is that I don't think the improved heat management is something very relevant with this car. The 15" steels are already more than adequate for such a light car with less than 400 hp. Unless you're adding a lot more aftermarket power, and you're Mario Andretti on a high-speed track in Texas during August, I think the standard brakes will hold up. Especially with proper pads/fluid.
 

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Yep, different stuff is relevant to different people. I ran a 2.5 Boxster with stock brakes over 10 years, 100+ track days, and several TT Championships. Those brakes held up fine with the right pads and fluids. They were also 1/2 the mass of GT4 rotors so a lot less heat sink capacity. Some guys couldn't wait to bolt on big brakes to those cars but were they really necessary? No. I probably will continue running std rotors on my Cayman and never need PCCBs either but in the end, we all want what we want. In all honesty, we probably don't really need 380 hp either. ;)
 
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Discussion Starter #16
Heresy! Heresy, I say.
Haha, word. I'm driving a 2015 Mustang GT at the moment, and even 435 hp seems a *liiittle* low for my liking. Granted, the GT4 will weigh 800 lbs less (although the Mustang has more aggressive gearing), but still.

Still, unlike some car guys, I *do* think there is such a thing as too much power... for me at least, heh. So I get what cajun is saying.
 

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Yep that thread massages 1data point to the nth speculative degree. It's not consistent with 1/2 dozen drivers in SoCal that have been running the same PCCB brake hardware for 4- 5 years.
It is however completely consistent with the experience in Porsche Supercup, which replace their PCCB rotors once every 3 track weekends. It's also consistent with many owners experiences ie the Pano article in November 2014. The only reason much has been made of that data is it's the best we've got for 3rd generation PCCBs. But we've got tons of data for previous generations, and it's nearly all damning. I'd like to see actual data from track rats that suggest otherwise (track miles, type of running, etc). The exception is obviously if you can keep the rotors from getting hot, but that's not practical for most.

Even if we assume actual life is triple the Supercup experience or Rennlist thread data (in some hands, maybe a brake friendly track), we still get roughly $10 per track mile in PCCB rotor and pad costs vs $2 per track mile for iron. The GT4 will keep the rotors cooler and may therefore be better, but for an average weight savings of ~32 lbs (assuming half worn iron rotors) and an essentially imperceptible behind the wheel difference that's a lot to spend, and a large risk to take, if you track your car consistently.

If you only autocross I can see some value, particularly if you're competitive. You will see a slight advantage vs the clock, and you'll essentially never wear them out.
 

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Agreed. I think the irony, is that the PCCBs are a better "value" for a street vehicle than a track car.

And there's a difference between PCA DE drivers taking their GT3 out a few times a year, and the racers that really beat the crap out of a GT3 on the track, as God intended. That second group will heat up the brakes exponentially more than the typical DE'r.

PCCBs do increase performance with lower weight and zero fade... but honestly, they are 99% marketing and a huge profit center for Porsche, both at initial purchase AND maintenance. The true performance improvements are minimal.
 

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Porsche says 50% weight savings on the rotors. That is significant... 10lbs per corner maybe. Even more significant is that some owners might go 100k miles before their first brake service. If you are a track rat they won't last so long but they will last maybe 5-10 times longer than stock brakes. Not cheap but good.

]
Porsche say that , but the small print is for like for like size !!! ccb are normall much bigger when speced !
 

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Agreed. I think the irony, is that the PCCBs are a better "value" for a street vehicle than a track car.

I am not sure of the justification to say this. I mean this honestly and not as a wise guy. I am a street only driver but the thought of PCCBs is relatively new to me. After doing a ton of research, it seems that nobody is really that impressed with them. Here are the conclusions that I have drawn.

1. The tires will limit the car's braking ability long before any PCCB advantage is realized.
2. Most people say there is an imperceptible difference in performance due to spinning and unsprung mass weight differences. For anyone but a top driver with mad mad skills, the difference will never really be realized.
3. Longevity may help on the street, but there is mixed data on this. You can replace the brakes and rotors twice (meaning three sets in total) for the same price as PCCBs.
4. At least on a GT4 you get a massive upgrade in rotor size. For the Spyder, you only get +10mm in the front for the same price as the GT4 or a Boxster S upgrade. Spyder owners get the least 'value' same amount of money.
5. There is a coolness factor to having them

For me, this easily indicates to leave the option selection box empty.
 
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