'82 SC winter project brake question / yes I have read the Ultimate Brake Thread

[cutline_joe]

Hello All,

I am starting to line up my winter projects and I have a caliper and rotor question. My stock SC calipers need to be rebuilt and the rotors replaced. And yes, brake bleed, good fluid, good pads are all already included in the equation. Mostly street, but I plan to do some DEs and really learn how to drive my car to its limits in the next few summers. I do not see a need to spend 3k now on braking power I will not even touch in the near future. I will spend the money when I can prove to myself that my driving ability warrants it.

Front:

I was thinking up just going to Carrera front calipers and rotors, they cost between the two is negligible. It seems to be a pretty common "update". Is there any disadvantage to doing this change? I haven't really found a list of cons for this change.

Rear:

I do not see or have been unable to find mention of people going to Carrera rear rotors and calipers on the SC, everyone seems to retain the stock. I am under the impression that this change requires a new MC from and 84-86, is that correct? Other than the MC is it a direct bolt on swap? Are there any disadvantages to making this change? In my rookie mind the larger Carrera caliper piston is a good thing and can't really hurt.

thanks,

- Joe

[Bob Kontak]

Joe - Don't do the Boxster upgrade. Too much noise when stopping while street driving. Also folks say it is too much caliper even for the larger Carrera rotor under stress.

I like the Carrera caliper idea but read lots of old posts first . When you search, enter your criteria into the advanced search area. Suggest loading "Bill Verburg" in the user cell and "brakes" in the keyword cell. That will keep you busy for a while.

This link talks of the Carrera calipers upgrade. Porsche 911 Brake Upgrade Question

[Flieger]

The Carrera rear pistons are too large and make for a rearward brake bias. This is why the pressure limiting valve was installed on the Carreras. keeping the SC rear calipers retains a safer front bias.

[cutline_joe]

Originally Posted by Flieger

The Carrera rear pistons are too large and make for a rearward brake bias. This is why the pressure limiting valve was installed on the Carreras. keeping the SC rear calipers retains a safer front bias.

This was what I thought after reading Bill V.'s page and it showed this:

Proportioning Valve (bar) 33
reduction factor 0.46

My thought was swapping to the 84-86 MC would solve the rear bias issue. I was under the impression that the proportioning was done in the MC, but it wouldn't be the first time I was wrong.

[Flieger]

Proportioning valve is separate. It does not actually "proportion" like an adjustable balance bar, just limits the maximum rear pressure. So, as you first appy pressure to the pedal, both front and rear are getting the same amount of force. The balance shifts once that maximum pressure is reached.