4 wheel disc brakes

Darter6 said

This is mostly for you linelock question.I did 4 wheel disc brakes on a 65 Belvedere with line lock. Instructions in the above posts,, Install line from MC to line lock solidnoid. From line lock to left right spliter for front brakes. Rear MC to adjustable prop valve directly to rear brake line.Now this was on a 65 so It was replacing a single master cylinder set up,no factory prop valve that used a 3 way spliter,,2 lines to the front brakes and one to the rear that was plugged off,now using the adjustable prop valve. On a 69(dual master) I believe it has a block with a brake light switch,set prop valve from the factory. I wish I had a 69 service manual to see if you need to bypass or if you can use it for the rear brakes. I'm sure some one will have that answer.

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see ive always seen them called prop valves but they are really safety valves, and sometimes a metering valve.

The safety valve is just the plunger that will block a circuit if you lose pressure (i.e. buster brake line)

The metering valve keeps the rear brakes from locking up from a pressure spike

Where are a prop block creates a restriction so you get less goods "throughout the curve" so to speak. So yes under hard braking the rears wont lock up (prop valve), but the rest of the time they don't have enough. This is where the valve I posted comes in, it allows full fluid pressure except for the spike of a panic stop that would cause lock up.

if anyone has the info on exactly what years had what that would be a great help. IMO if all the valve is on the frame rail/under master is a metering valve and/or safety valve use it (new or rebuilt of course)