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Benino · Posted: Sat Jul 30, 2005 8:16 am Post subject: brake proportioning valve

I want to clean out or replace my proportioning valve(s) for the brakes on my 1980 N/A. Where is it located? Is there just one or is there one for each rear brake? Anyone replaced it before? My rears brakes seem to be too strong.

(front calipers not locked up, no leaking, working master cylinder swapped from car with perfectly working brakes, brakes bled multiple times, new front disks rear drums, new front pads rear shoes)
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1980 Porsche 924 N/A USA
1980 Porsche 924 turbo USA
1987 Porsche 944S USA

Gram · Posted: Sat Jul 30, 2005 8:27 am Post subject:

Wasn't aware there is one on 924's..
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'82 924 NA Euro (hers)
'98 Audi A4 TDI (ours)

Benino · Posted: Sat Jul 30, 2005 11:44 am Post subject:

I don’t know for sure that it has one but since it's a system with 2 diagonal circuits, and 3 lines come out of the master cylinder, that means at least one of the lines includes a front and rear wheel, so it seems to me it would have to have a proportioning valve. Nobody knows where it is or has ever worked on it?
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1980 Porsche 924 N/A USA
1980 Porsche 924 turbo USA
1987 Porsche 944S USA

924RACR · Posted: Sat Jul 30, 2005 11:37 pm Post subject:

No, it doesn't have one. The proportioning is built into the sizing of the hydraulic components. You may need to either rebuild or replace your calipers and/or slave cylinders - most likely the calipers aren't working strongly enough. When were the hoses last replaced?
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Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Joes924Racer · Posted: Sun Jul 31, 2005 4:20 pm Post subject:

I was gonna add one..still might just to see what it does.
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1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

924RACR · Posted: Mon Aug 01, 2005 12:09 am Post subject:

Not recommended. All it's going to do, unless you put in a different master cylinder, is make your rear brakes even less effective.
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype