Pccb to Brembo III update
#16
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I'm guessing your English is a lot better than my Deutsch, so please indulge me in elaborating on what you've posted about PCCBs versus steels, especially in terms of cost and durability. It sounds like you've had about about the equivalent of six or maybe ten track days -- it's hard to compare laps at the ring versus a typical track since the ring is intense and hard on brakes. You've replaced the pads four times and the rotors are still the original units.
That's about consistent with my experience -- for ten to twenty track days, the rotors are fine and pad wear is expensive.
The more the front pads wear, the faster they "wedge" until the risk is having the leading edge of the pad backing plate destroy the rotor before the wear indicator sounds the alarm.
My concern is that when the rotors reach a threshold of wear (somewhere around 20 days) the outer friction surface deteriorates, abrasion accelerates, the thin laminate outer layer decomposes and the rotor is lost.) This is not a matter of anecdote, driver-error or hearsay, it's been happening with each "generation" of PCCB since the glorious, infamous 996 GT2 circa 2002.
If there are drivers out there running PCCBs on the track for more than one year and more than 20 or say 30 days driven at serious pace (let's says within five seconds per minute of lap records for a GT3 street car at the given venue) then I'm sure a lot of PCCB owners with their US$20K paperweights would like to know they've simply got a defective product due to production line quality issues, which should be replaced under warranty.
That's about consistent with my experience -- for ten to twenty track days, the rotors are fine and pad wear is expensive.
The more the front pads wear, the faster they "wedge" until the risk is having the leading edge of the pad backing plate destroy the rotor before the wear indicator sounds the alarm.
My concern is that when the rotors reach a threshold of wear (somewhere around 20 days) the outer friction surface deteriorates, abrasion accelerates, the thin laminate outer layer decomposes and the rotor is lost.) This is not a matter of anecdote, driver-error or hearsay, it's been happening with each "generation" of PCCB since the glorious, infamous 996 GT2 circa 2002.
If there are drivers out there running PCCBs on the track for more than one year and more than 20 or say 30 days driven at serious pace (let's says within five seconds per minute of lap records for a GT3 street car at the given venue) then I'm sure a lot of PCCB owners with their US$20K paperweights would like to know they've simply got a defective product due to production line quality issues, which should be replaced under warranty.
#17
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FWIW, if anyone is experience tapered pad wear with the 6 piston calipers, there is a larger issue at hand. With the differentially sized pistons, pad taper is not an issue. I don't know of anyone running in ALMS GT/GTC or Grand Am GT with a pad taper problem. And I would suggest they are running the cars/brakes/pads harder than most here (no offense to anyone intended)
As to the Endless fluid, I also know quite a number of teams have switched over ot the Prospeed RS683 and have found a noticable difference in the overall firmness and consistency of the pedal.
As to the Endless fluid, I also know quite a number of teams have switched over ot the Prospeed RS683 and have found a noticable difference in the overall firmness and consistency of the pedal.
#18
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I don't know of any GT3/RS that DON'T have tapering in front, besides Jim above. It is noticable after 2 days, say 300 track miles and have to be flipped after 4 days. Most drivers I know run Pagid 29 on steels 07-11GT3/RS.
One could argue that we create more heat because cars are heavier, maybe even brake longer, harder because over slowing the car and bad braking techiques and less front cooling...Add to that lot's of Sbring driving and you have a worse case scenario for an indentical caliper disc setup..
I'm working on all 3 factors :-)
One could argue that we create more heat because cars are heavier, maybe even brake longer, harder because over slowing the car and bad braking techiques and less front cooling...Add to that lot's of Sbring driving and you have a worse case scenario for an indentical caliper disc setup..
I'm working on all 3 factors :-)
#19
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FWIW, if anyone is experience tapered pad wear with the 6 piston calipers, there is a larger issue at hand. With the differentially sized pistons, pad taper is not an issue. I don't know of anyone running in ALMS GT/GTC or Grand Am GT with a pad taper problem. And I would suggest they are running the cars/brakes/pads harder than most here (no offense to anyone intended)
As to the Endless fluid, I also know quite a number of teams have switched over ot the Prospeed RS683 and have found a noticable difference in the overall firmness and consistency of the pedal.
As to the Endless fluid, I also know quite a number of teams have switched over ot the Prospeed RS683 and have found a noticable difference in the overall firmness and consistency of the pedal.
You're referring to cross-drilled steel and ceramic as well as slotted steels?
ps. there is a known cause of the tapering.
I don't know of any GT3/RS that DON'T have tapering in front, besides Jim above. It is noticable after 2 days, say 300 track miles and have to be flipped after 4 days. Most drivers I know run Pagid 29 on steels 07-11GT3/RS.
One could argue that we create more heat because cars are heavier, maybe even brake longer, harder because over slowing the car and bad braking techiques and less front cooling...Add to that lot's of Sbring driving and you have a worse case scenario for an indentical caliper disc setup..
I'm working on all 3 factors :-)
One could argue that we create more heat because cars are heavier, maybe even brake longer, harder because over slowing the car and bad braking techiques and less front cooling...Add to that lot's of Sbring driving and you have a worse case scenario for an indentical caliper disc setup..
I'm working on all 3 factors :-)
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TrakCar, I don't know you personally so my comments are certainly to a degree, generalized. But I also know pad taper isn't/wasn't an issue for any of the teams running in ALMS GTC at Sebring 12 hrs. And I'm reasonal sure they drove farther than 300 miles in the 12 hrs. The word in the paddock was the teams running the Endless pads didn't even need to make a pad change in 12 hrs. (I have no vested interest in Endless or any other brake pad mfr)
#21
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Autokurl, you are on to something.
Racers don't have that much of an issue, I know.
It could be because above reasons and even as simple as grippier slicks = shorter braking distance and higher corner speed = even less braking distance.
It may be worse on the Pagid R29.
I was interested in something else not because of wear, but because of loss of bite.
After 6 days, 24 sessions and 1000 track miles the pads are still 35-50% (after flipping them) but they just won't stop the car anymore, pedal also gets softer because I think more heat in thinner pad, but the real problem was that they just don't bit, I'm not even sure if I can get to ABS anyone when they get hot enough after so many heat cycles..
Keep in mind I am looking for a lower cost per track day pad. I will give up some performance to save
$$, but after 6 days I just have to adjust my driving too much to compensate for the lesser braking of the car that I lose a few seconds, but it also gets annoying.
I have not myself, but another customer of Orbit tested the Endless pads used in the endurance races. They lasted much longer, but also lost bite before they wore out, it just took longer and because higher cost there is no benefit for cost per session. I have not gotton measurements of the pad thickness to know about how much they tapered.
I am now testing PFC 08 pads (And rotors), but only have one day on them. I will have 11 or 12 days on them by the end of July, so I will know more about PFC holding up by then.
The PFC pads cost roughly the same as the Pagids, the rotor and had combo cost double the OEM rotors (Good for 16-20 days) but the replacement disc cost the same and I expect double life out of the slotted discs but I will find out. Rear OEM discs are good for 40 days anyway, so no point in upgrading those.
Orbit ran a GT3 last week at PBIR, also a brake killing track with extra brake ducting. Everything seemed to work well but too early to tell, more propre testing is needed and I hope to add it after July. Maybe it helps, I figure it can't hurt.
Racers don't have that much of an issue, I know.
It could be because above reasons and even as simple as grippier slicks = shorter braking distance and higher corner speed = even less braking distance.
It may be worse on the Pagid R29.
I was interested in something else not because of wear, but because of loss of bite.
After 6 days, 24 sessions and 1000 track miles the pads are still 35-50% (after flipping them) but they just won't stop the car anymore, pedal also gets softer because I think more heat in thinner pad, but the real problem was that they just don't bit, I'm not even sure if I can get to ABS anyone when they get hot enough after so many heat cycles..
Keep in mind I am looking for a lower cost per track day pad. I will give up some performance to save
$$, but after 6 days I just have to adjust my driving too much to compensate for the lesser braking of the car that I lose a few seconds, but it also gets annoying.
I have not myself, but another customer of Orbit tested the Endless pads used in the endurance races. They lasted much longer, but also lost bite before they wore out, it just took longer and because higher cost there is no benefit for cost per session. I have not gotton measurements of the pad thickness to know about how much they tapered.
I am now testing PFC 08 pads (And rotors), but only have one day on them. I will have 11 or 12 days on them by the end of July, so I will know more about PFC holding up by then.
The PFC pads cost roughly the same as the Pagids, the rotor and had combo cost double the OEM rotors (Good for 16-20 days) but the replacement disc cost the same and I expect double life out of the slotted discs but I will find out. Rear OEM discs are good for 40 days anyway, so no point in upgrading those.
Orbit ran a GT3 last week at PBIR, also a brake killing track with extra brake ducting. Everything seemed to work well but too early to tell, more propre testing is needed and I hope to add it after July. Maybe it helps, I figure it can't hurt.
#22
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The two best pads I have run are the Ferodo DS2500 for the street and the Raybestos ST41 on the track, but both of those were in 4 pison calipers. I couldn't tell ya if either is produced in the FMSI 991 size you need for the 6 piston. I have a friend at Raybestos... I'll see what I can find out.
FWIW the ST41 was incredible if you like a High Torque pad. When they were warmed up they would literally stand the car on it's nose! Far, far better pad (for my driving perferences) than the Pagids I have run (admittedly I have only driven the Orange and the Blacks) Andthe Raybestos are cheap relative to the other pads. For example $146/set for the old Big Reds.
I'm now wondering if the earlier 6 piston had the taper issue. The reason I mention this is there is a difference in the piston sizes. the early 6 piston was 38/32/28 mm. I never had any issues with pad taper with this caliper. The current caliper is 32/30/28 mm. So the trailing most piston being smaller would be applying less force i.e. the leading edge to trailing edge differential would be less.
I take it you had no issues with pad taper with the Stoptech STR brakes, correct?
FWIW the ST41 was incredible if you like a High Torque pad. When they were warmed up they would literally stand the car on it's nose! Far, far better pad (for my driving perferences) than the Pagids I have run (admittedly I have only driven the Orange and the Blacks) Andthe Raybestos are cheap relative to the other pads. For example $146/set for the old Big Reds.
I'm now wondering if the earlier 6 piston had the taper issue. The reason I mention this is there is a difference in the piston sizes. the early 6 piston was 38/32/28 mm. I never had any issues with pad taper with this caliper. The current caliper is 32/30/28 mm. So the trailing most piston being smaller would be applying less force i.e. the leading edge to trailing edge differential would be less.
I take it you had no issues with pad taper with the Stoptech STR brakes, correct?
#23
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I've not run them on a Porsche, but I've used them for 30,000 miles on the street in my M3 CSL with AP six pot calipers come street rain and shine, always powerfull and always consistent.
#24
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FWIW, if anyone is experience tapered pad wear with the 6 piston calipers, there is a larger issue at hand. With the differentially sized pistons, pad taper is not an issue. I don't know of anyone running in ALMS GT/GTC or Grand Am GT with a pad taper problem. And I would suggest they are running the cars/brakes/pads harder than most here (no offense to anyone intended)
As to the Endless fluid, I also know quite a number of teams have switched over ot the Prospeed RS683 and have found a noticable difference in the overall firmness and consistency of the pedal.
As to the Endless fluid, I also know quite a number of teams have switched over ot the Prospeed RS683 and have found a noticable difference in the overall firmness and consistency of the pedal.
Taper is affected not only by the caliper piston sizing, but also the rigidity of the caliper itself (which it loses over time), and the integrity of the caliper mounting system as well. Sometimes certain tracks cause taper on certain inners or outers. Some pad compounds have certain taper tendencies. Sometimes tire performance can affect taper and brake performance. Tires are a good part of braking.