Brake Upgrade, Fuchs options, RS Clone
#1
Instructor
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Hello
I'm in the process of building a '73RS Clone from a '70T platform. Currently, I have 7x15 Front/ 8x15 Rear Fuchs Wheels and Brakes from a 1973 911S. I want to develop more stopping power, but I really want to stay with the traditional Porsche/Fuchs look. Does anyone make a big brake kit that will fit inside a 15" wheel? If I go w/16" Fuchs wheels, does this open up my options? I heard there is a kit being made that allows the use of Boxster Brakes. Anyone have any experience with this conversion? Will it fit inside 15" or 16" wheels? Looking forward to your feedback
Thanks
Jim Florance
I'm in the process of building a '73RS Clone from a '70T platform. Currently, I have 7x15 Front/ 8x15 Rear Fuchs Wheels and Brakes from a 1973 911S. I want to develop more stopping power, but I really want to stay with the traditional Porsche/Fuchs look. Does anyone make a big brake kit that will fit inside a 15" wheel? If I go w/16" Fuchs wheels, does this open up my options? I heard there is a kit being made that allows the use of Boxster Brakes. Anyone have any experience with this conversion? Will it fit inside 15" or 16" wheels? Looking forward to your feedback
Thanks
Jim Florance
#2
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You might want to read <a href="http://home.nycap.rr.com/wmv/generalbrmd.htm" target="_blank">this.</a>
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#3
Technical Specialist
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Boxster brakes are fine for street usage, however, if you go near a track, I wouldn't recommend them. On the track, they can over power the rotors, causing boiled brake fluid and other ills.
#4
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</font><blockquote><font size="1" face="Verdana,Tahoma,Arial,Helvetica,Geneva">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Originally posted by Jim Florance:
<strong>Hello
I'm in the process of building a '73RS Clone from a '70T platform. Currently, I have 7x15 Front/ 8x15 Rear Fuchs Wheels and Brakes from a 1973 911S. I want to develop more stopping power, but I really want to stay with the traditional Porsche/Fuchs look.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Jim-
It's the tires that stop the car, not the brakes. Your "stopping power" with '73S brakes is sufficient for those wheels, all you need is adequate thermal control so you don't overheat the system. Install a good cooling kit and use good race pads with fresh high-temp fluid and you should be fine on all but the hottest days on tracks that are extremely tough on brakes.
If you are determined to upgrade the brakes anyway, the only setup that will meet your needs is the early 930 calipers and rotors. Be prepared to open your wallet very wide. $2-3,000 will do it, depending on how much work you do yourself.
My 7 and 8" Fuchs still fit over the 930 brakes on my '73RS clone, but they require a 7mm spacer to do it, otherwise there is interference between the caliper and spokes. I only use them for street driving anymore. On the track, I use 8 & 9 x 16" Fuchs, which have greater caliper overhang clearance, negating the need for a spacer. The 8 x 16s must be the '86 944T Fuchs with 23mm offset to fit a narrow body 911 in the front. These wheels are rather pricey, so add another $2K to the cost of this upgrade.
Again, without adding more tire or more power to your car, your existing brakes are quite sufficient in almost all conditions, and I would seriously think about using the money elsewhere. I ran stock SC brakes (same size as 'S') for several years with a 205hp 3-liter motor and never had a fade problem.
Good luck on your project,
TT
<strong>Hello
I'm in the process of building a '73RS Clone from a '70T platform. Currently, I have 7x15 Front/ 8x15 Rear Fuchs Wheels and Brakes from a 1973 911S. I want to develop more stopping power, but I really want to stay with the traditional Porsche/Fuchs look.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Jim-
It's the tires that stop the car, not the brakes. Your "stopping power" with '73S brakes is sufficient for those wheels, all you need is adequate thermal control so you don't overheat the system. Install a good cooling kit and use good race pads with fresh high-temp fluid and you should be fine on all but the hottest days on tracks that are extremely tough on brakes.
If you are determined to upgrade the brakes anyway, the only setup that will meet your needs is the early 930 calipers and rotors. Be prepared to open your wallet very wide. $2-3,000 will do it, depending on how much work you do yourself.
My 7 and 8" Fuchs still fit over the 930 brakes on my '73RS clone, but they require a 7mm spacer to do it, otherwise there is interference between the caliper and spokes. I only use them for street driving anymore. On the track, I use 8 & 9 x 16" Fuchs, which have greater caliper overhang clearance, negating the need for a spacer. The 8 x 16s must be the '86 944T Fuchs with 23mm offset to fit a narrow body 911 in the front. These wheels are rather pricey, so add another $2K to the cost of this upgrade.
Again, without adding more tire or more power to your car, your existing brakes are quite sufficient in almost all conditions, and I would seriously think about using the money elsewhere. I ran stock SC brakes (same size as 'S') for several years with a 205hp 3-liter motor and never had a fade problem.
Good luck on your project,
TT
#5
Instructor
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Bill:
I read the site you provided me, Wow, lots of good information. I had planned on using DOT4 fluid and Pagid discs for at least the next year before doing anything drastic with replacing my brakes, that site only cemented my plans. I already do have s calipers. I will be replacing my rotors as advised on that site. Thanks for the link!
Tom:
Your position is very compelling, and I agree with everything you said, I understand that tires are the key to stopping the car. I am planning to use 7"wide front, 9"wide in rear,and will use DOT R Tires when out at track events. I should have made that clear. The reason I was looking for information about brake fit was that I am now in the market for my wheels and wanted to know if while I was looking for 16" fuch wheels and come across a set of 9"x15" wheels, would they accomdate bigger brakes as a future upgrade.
I read the site you provided me, Wow, lots of good information. I had planned on using DOT4 fluid and Pagid discs for at least the next year before doing anything drastic with replacing my brakes, that site only cemented my plans. I already do have s calipers. I will be replacing my rotors as advised on that site. Thanks for the link!
Tom:
Your position is very compelling, and I agree with everything you said, I understand that tires are the key to stopping the car. I am planning to use 7"wide front, 9"wide in rear,and will use DOT R Tires when out at track events. I should have made that clear. The reason I was looking for information about brake fit was that I am now in the market for my wheels and wanted to know if while I was looking for 16" fuch wheels and come across a set of 9"x15" wheels, would they accomdate bigger brakes as a future upgrade.
#6
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As I wrote on the previously linked page the 930 calipers and rotors will work in 15s radially. The transverse fit depends on wheel width, 9s are no problem, but 8s and 7s need progressively more machine work on the caliper.
Here is a pic of a 930 caliper and rotor in a 15
<img src="http://www.pelicanparts.com/MotorCity/wmv/DeMan_Motorsport%20030_small.jpg" alt=" - " />
Here is a pic of a 930 caliper and rotor in a 15
<img src="http://www.pelicanparts.com/MotorCity/wmv/DeMan_Motorsport%20030_small.jpg" alt=" - " />