911 BRAKES

I read your 911 project articles hoping you would do something beyond restoration. I am currently using my 86 Carrera for AutoX and would like to see your assessment of how the performance could be upgraded.

I probably will not use my Carrera for constant racing just AutoX. I have used it in DE events but had no problem with brake fade or stopping after 20-30 minutes of hard driving on DOT tires. I have since reduced the weight of the car by about 200 lbs and plan to upgrade the suspension to stiffer Tbars and shocks. I was interested in using some of the 930 parts maybe the larger brakes (11.1F 11.4R Carrera compared to 11.9F 12.4R with aluminum callipers and 50% more pad surface for turbo 930).

I was told that under heavy use racing the rotors will not wear as fast with the larger turbo pads and rotors. The heat sink capability of the rotors is greater.

[I]The 930 setup on most cars, even dedicated race cars, has a long lifespan for pads and rotors.[/I]

But there are now ceramic coatings that can improve heat dispersion. What I was interested in was making the current stock setup work better using less money (Turbo brakes are $5000).

Has anyone compared the two systems for braking benefit or compared a revised stock system to a turbo system?

If it's just for autocross then the hardest way to get better times would be to upgrade the brakes. You say they're good enough for light DE duty which means they're WAY more than good enough for any kind of AutoX.

Put your money into suspension and power mods.

911 brakes are pretty damn good out of the box. You took 200lbs out making them even better. Upgrade the pads to something that works for the temp range you generate in a parking lot and spend the money making it corner flatter.

Or... more simply, +1 GRMH.

We're discussing some brake upgrades for that car, but I have a question for you: What specific braking problem are you trying to overcome? It sounds like you're looking for longer pad life, but just wanted to make sure.

You can replace a lot of Carrera Brake pads for the cost of a brake upgrade to 930 parts. the 32mm 930 rotors are also significantly heavier than your current setup. However, the thermal performance can not be beat.

You can drive a 930 setup hard all day long and it will not have any issues as long as you are braking properly.

the best choice of upgrade for you is cooling ducts. This will significantly reduce pad and rotor temperatures, prevent pad transfer and put the pads in a better operating temperature. This also makes them last longer.

Track VS AX? You do need different pad compounds. AX you need more of a street pad with lots of initial friction when cold and some high temp capability depending on the course length in your locale. Track is best with a higher temp pad.

As David said, what about your current brake setup are you trying to fix?

jpnovak wrote: the best choice of upgrade for you is cooling ducts. This will significantly reduce pad and rotor temperatures, prevent pad transfer and put the pads in a better operating temperature. This also makes them last longer.

Great idea, cheap, negligible increase in unsprung weight, and it will probably give as big an improvement as the big brakes.

Good Ideas. I was trying to just replace worn rotors and pads...tens years of wear. I have since done a replacement with stock rotors and calipers with the calipers getting restored and plated. I also had the rotors/calipers ceramic coated (inner surface) to promote heat dissipation. They are working fine and there is no rust. I may try the cooling ducts for DE.

That was quite the power nap