Lightweight Brake Bells (Hats) For 964 (And A Surprise)
12-15-2002, 12:08 AM
#1
Lightweight Brake Bells (Hats) For 964 (And A Surprise)
The attached pictures might be of interest re weight reduction: for a 964, lightweight 2618 high temperature aluminum brake bells with a titanium bobbin mounting system creating an air gap.
12-15-2002, 10:33 AM
#2
Addict
Rennlist Member
Rennlist Member
Nice set up - Where did you get the pieces for this, what do they cost and do they have sizes for the 964 Turbo.
What does the rotor and housing weigh compared to conventional?
Titanium bobbin - you mean the screws and nuts?
What pads do you run with MMC rotors?
What does the rotor and housing weigh compared to conventional?
Titanium bobbin - you mean the screws and nuts?
What pads do you run with MMC rotors?
12-15-2002, 11:19 AM
#3
We made the brake bells (hats). These particular ones would fit a Type 964 Turbo. Hats could be made for any Porsche (or other car) -- assuming proper clearance for a particular disk and a corresponding proper caliper. The rotors are not metal matrix composite (MMC), the surprise is that they are carbon ceramic. In fact, I believe that this is the first usage of carbon ceramics for a Type 964.
The weight of the rotor (in this instance, a 14 inch one) is barely a third of the metal equivalent. As to the bell, it weighs approximately one pound, i.e., about a third that of the stainless steel bells currently used by Porsche in connection with the PCCB. The reason Porsche uses a stainless steel version (other than durability) is that, particularly in racing, carbon ceramic disks could see temperatures in excess of 1000 degrees C and aluminum melts at 660 degrees C. Titanium, on the other hand, melts at 1660 degrees C. Hence, by using titanium as the mounting interface and by creating the air gap, lighweight aluminum bells are usable.
The "bobbin" terminology refers to the method of mounting, not the fact that certain of the components (i.e., the ones gold in color due to a protective coat of ti nitride) are titanium. This system, by the way, is similar to the mounting system generally used on F1 cars which use carbon carbon disks.
As to pads, the pads currently available with carbon ceramic brake systems tend to have shortcomings related to the heat that they are forced to absorb due to the nature of carbon ceramics as an insulator. This having been said, giving what is currently available, I would use the Pagid RS-19 compound until a better answer is available (in a few months).
Finally, please note that one cannot simply change metal rotors for carbon ceramics and expect the system to work properly or safely. It is, after all, a system, and, particularly given heat and dynamics issues, the calipers, fluid, hydraulics, ABS, wheel size, tire compound, etc., etc. all must be addressed. Additionally, when this unsprung and rotating much weight is eliminated from each corner, suspension components require alteration for optimal performance.
Lastly, the system pictured above includes a titanium certerlock system which is not required to be used with the carbon ceramics.
P.S. Although MMC rotors have been produced in the past, I know of no credible current application. Titanium rotors are, however, used in certain race applications, i.e., World of Outlaws. For weight and other considerations, I would favor carbon ceramics or carbon carbon if they were allowed in the particular racing class.
The weight of the rotor (in this instance, a 14 inch one) is barely a third of the metal equivalent. As to the bell, it weighs approximately one pound, i.e., about a third that of the stainless steel bells currently used by Porsche in connection with the PCCB. The reason Porsche uses a stainless steel version (other than durability) is that, particularly in racing, carbon ceramic disks could see temperatures in excess of 1000 degrees C and aluminum melts at 660 degrees C. Titanium, on the other hand, melts at 1660 degrees C. Hence, by using titanium as the mounting interface and by creating the air gap, lighweight aluminum bells are usable.
The "bobbin" terminology refers to the method of mounting, not the fact that certain of the components (i.e., the ones gold in color due to a protective coat of ti nitride) are titanium. This system, by the way, is similar to the mounting system generally used on F1 cars which use carbon carbon disks.
As to pads, the pads currently available with carbon ceramic brake systems tend to have shortcomings related to the heat that they are forced to absorb due to the nature of carbon ceramics as an insulator. This having been said, giving what is currently available, I would use the Pagid RS-19 compound until a better answer is available (in a few months).
Finally, please note that one cannot simply change metal rotors for carbon ceramics and expect the system to work properly or safely. It is, after all, a system, and, particularly given heat and dynamics issues, the calipers, fluid, hydraulics, ABS, wheel size, tire compound, etc., etc. all must be addressed. Additionally, when this unsprung and rotating much weight is eliminated from each corner, suspension components require alteration for optimal performance.
Lastly, the system pictured above includes a titanium certerlock system which is not required to be used with the carbon ceramics.
P.S. Although MMC rotors have been produced in the past, I know of no credible current application. Titanium rotors are, however, used in certain race applications, i.e., World of Outlaws. For weight and other considerations, I would favor carbon ceramics or carbon carbon if they were allowed in the particular racing class.
12-15-2002, 12:42 PM
#4
Instructor
Join Date: Dec 2001
Location: germany
Posts: 238
Likes: 0
Received 0 Likes
on
0 Posts
hallo Robert
You should also say that these Brakes are not for Streetuse because the Operate only under Temperature proper .
This looks like a very nice set up from high Craftmanship and materials ,but it is a Track only thing, isnt it ?
harald
You should also say that these Brakes are not for Streetuse because the Operate only under Temperature proper .
This looks like a very nice set up from high Craftmanship and materials ,but it is a Track only thing, isnt it ?
harald
12-15-2002, 01:18 PM
#5
Actually, Harald, you are incorrect. If these disks were carbon carbon, you would be correct as this material only operates at full efficiency at temperature. Carbon ceramics, however, operate at all temperatures which is why Porsche makes them standard on the GT2, offers them on the Type 996 Turbo and C4S and why they will be standard on the Carrera GT and are standard on the Ferrari Enzo.
12-15-2002, 02:15 PM
#6
Racer
Join Date: Jun 2001
Location: The Netherlands
Posts: 283
Likes: 0
Received 0 Likes
on
0 Posts
Robert, some very racy brakes indeed and really impressive weight savings. These and most of the other products pictured in your posts exude quality, workmanship and attention to detail that is simply amazing. Respect.
In your own words: "To demonstrate to three specific audiences – semi and professional racers and certain manufacturer personnel -- what can be done for dramatic improvements to sportscar racing, both in terms of rapid high end design and in terms of being able to rapidly and efficiently manufacture small numbers of specialty items (as, for example, would be required under ACO homologation rules)."
I can't help but wonder how far does engineering development and testing of these parts stretch? Are they unique protoypes or is there more to it? Do structural parts conform to design and engineering standards? Is reliability of the final product with all of the parts combined on the agenda? Shooting from the hip but are you considering such issues as fatigue performance, environmental ageing, vibration analysis, thermal performance, damage tolerance, etc.etc.? I'm thinking more of the carbon composite construction parts in previous posts and expect the answers will be different for these brakes.
Sincerely,
Nol
In your own words: "To demonstrate to three specific audiences – semi and professional racers and certain manufacturer personnel -- what can be done for dramatic improvements to sportscar racing, both in terms of rapid high end design and in terms of being able to rapidly and efficiently manufacture small numbers of specialty items (as, for example, would be required under ACO homologation rules)."
I can't help but wonder how far does engineering development and testing of these parts stretch? Are they unique protoypes or is there more to it? Do structural parts conform to design and engineering standards? Is reliability of the final product with all of the parts combined on the agenda? Shooting from the hip but are you considering such issues as fatigue performance, environmental ageing, vibration analysis, thermal performance, damage tolerance, etc.etc.? I'm thinking more of the carbon composite construction parts in previous posts and expect the answers will be different for these brakes.
Sincerely,
Nol
12-15-2002, 02:44 PM
#7
Nol:
Your points are very well taken. And, in fact, the factors you delineated, and many more, are taken into account for, as might be now evident, this project is somewhat more than but an amateur effort. This having been said, different considerations are appropriate for different components. For example, we just completed a set of aluminum lithium calipers to be used with the carbon ceramics -- and, other than being done in conjunction with one of the leading racing brake engineers in the world (with all of the years of knowledge and experience that this brought to bear), the calipers were subjected to more than 250,000 highly stressed cycles on a test rig before they would be put onto a car.
Additionally, certain of the parts I have posted on Rennlist are designed for street/track use and, as such, an extra margin of safety is intended to be built in. If, on the other hand, a part is purely for professional race use, one might feel more comfortable in stressing the component a bit more as its expected life is shorter and it is expected to be subjected to constant review and maintenance.
Your points are very well taken. And, in fact, the factors you delineated, and many more, are taken into account for, as might be now evident, this project is somewhat more than but an amateur effort. This having been said, different considerations are appropriate for different components. For example, we just completed a set of aluminum lithium calipers to be used with the carbon ceramics -- and, other than being done in conjunction with one of the leading racing brake engineers in the world (with all of the years of knowledge and experience that this brought to bear), the calipers were subjected to more than 250,000 highly stressed cycles on a test rig before they would be put onto a car.
Additionally, certain of the parts I have posted on Rennlist are designed for street/track use and, as such, an extra margin of safety is intended to be built in. If, on the other hand, a part is purely for professional race use, one might feel more comfortable in stressing the component a bit more as its expected life is shorter and it is expected to be subjected to constant review and maintenance.
Trending Topics
12-15-2002, 10:56 PM
#8
Racer
Join Date: Jun 2001
Location: The Netherlands
Posts: 283
Likes: 0
Received 0 Likes
on
0 Posts
Bob,
Thanks for the reply, so fatigue/performance testing as well. Somehow I now see how this is the one answer to my query consistent with what we see and what you posted before, awesome.
Looking forward to your next post,
Enjoy <img src="graemlins/burnout.gif" border="0" alt="[burnout]" />
Nol
Thanks for the reply, so fatigue/performance testing as well. Somehow I now see how this is the one answer to my query consistent with what we see and what you posted before, awesome.
Looking forward to your next post,
Enjoy <img src="graemlins/burnout.gif" border="0" alt="[burnout]" />
Nol
