First time owner working on the brake system and found this regarding the proportioning valve effects:
1) S/N 9193
2) 16,900 total miles. Inactive for last 18 years.
3) OEM Girling calipers with Textar pads. 1 piston aft, 4 piston front.Solid rotors.
4) Previous owner never worked on the brake system so I suspect it is all factory original.
I am new to Panteras and no expert on auto brake systems. I noticed the wear pattern on the pads and my first thought was that the front brakes are not working. The front rotors show absolutely no wear but I have not measured them.
I was reading the Dec. 2011 Sticky 5 post On the PV (proportioning valve)and thought this was a good example of it's operation.
I would think that if you were trying to balance a unbalanced (4 piston fnt. to 1 piston rear) brake system by use of the PV that you would have made it adjustable.
I have yet to drive the car but from what I'm seeing the brakes must have been poor at best.
As is I would think the system would benefit from removal of the PV. You need the fnt. brakes working.
QUESTION, does anyone have a diagram or discription of how the PV works ?
I would like to think on it awhile without taking it apart. Also not done reading the post or others on the subject.
Trying to keep the car original but stopping is a priority. Not that we'll ever see second or third gear here in LA traffic.
Last thought, as is the unadjustable PV seems to me like a patch for a poorly designed / way unbalanced brake system. But I'm a retired light aircraft mechanic, not a auto brake expert. From what I've seen on other cars the front brakes are most always bigger than the rear. And that's for a reason so why the PV ?
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