just got through with "diskin" the rear 14bolt. can't get good pressure in the pedal. It's real slow and doesn't work worth a crap. I've got the off-again brake booster and MC. they said to get rid of the prop valve. but they are the only ones saying that. What gives???BTW it worked great with the drums. Thanks.
ps i stripped the o-rings out of the prop valve but that didn't work

i wish i knew i just did the same thing and used a corvette mater cylinder and i have poo for a pedal i bled and bled and well i still have no pedal:nuke:

My pedal pressure is that great either. The brakes still bring everything to stop fairly well, but there is much room for improvement. I havent really decided, yet, how I plan to try and improve the pedal pressure and overall brake performance.
I can tell you, from my experience, that the rear brakes alone wont hold the rig. I tried to use my cutting brakes, on a steep drop off, durring the CalROCS competition, they let go,...and I went for a nose dive. :eek:

Gravity bleed, take the rear calipers off and move them around(turning side to side, upside down, ect) with the bleeder open. 95% chance you got air stuck in the caliper.
If you took the guts out of the stock P valve, your front and rear systems are now combined, not good. If you get one leak in any part of the system, all your brakes are gone. I run a line from the MC to the front and another from MC to the rear with an adjustable Pvalve.

Originally posted by jeepmodman
i wish i knew i just did the same thing and used a corvette mater cylinder and i have poo for a pedal i bled and bled and well i still have no pedal:nuke:

Remove stock pro valve ,,Add after market Pro valve If needed
later if too much rear braking

what size calipers in the rear??

I use 3/4 1/2 ton type GM caliper's
and Hydro boost and Corvette master ,,
but the Master need's to have No residual valve or ten PSI valve
this is cutting off proper operation to rear brakes

Adam,

A drum brake residual pressure valve holds 10 lbs of pressure in the system and can cause the disc brakes to drag. Doesn't sound like the problem here(yet anyway). The disc RP valves hold 2 lbs but I don't use either valve(removed from MC) and the brakes work very good.

Originally posted by Adam Ant


Remove stock pro valve ,,Add after market Pro valve If needed
later if too much rear braking

what size calipers in the rear??

I use 3/4 1/2 ton type GM caliper's
and Hydro boost and Corvette master ,,
but the Master need's to have No residual valve or ten PSI valve
this is cutting off proper operation to rear brakes

Adam,

Im running the same combo as you are Adam, no prop, nor residuals, nothing. Brakes nice and evenly too with the smaller rear calipers.

i run 4 wheel discs on my d60 and 14bolt. mine stops great! but then again i have a hydroboost setup. :D

I removed the prop valve and replaced it with new lines from the mc to where the pv was, 5/16 for front, and 1/4 rear. put a T for the front and barreled the rear to the stock line. the front is a chevy d60 and the rear is a 14b ff with 3/4 ton calipers and rotors.I replaced the lines on the rear end with 3/16 hard lines and chevy nova rubber lines(they say 2wire 1/8 on them) the mc is a navaho 1 1/4 inch with a 9" booster. off-again (where I bought it) says it should work fine. the rear res. is smaller than the front res. ???? A guy at Master power brakes said that my mc was no good that his was bored out special for guys like us. A military mechanic friend of mine said that the mc was wrong also and he didn't even look at it. He knew when i said that I could pump up the brakes fine with the motor off but when cranked up it went to crap. he said something about a safety switch in the mc???? I've pumped a ton of brake fluid through this thing and the bleeders are on the very top of the calipers. It is hard to believe there is any air in the system. If something looks fishy in my stuff let me know. THANKS

I'd have to agree with your buddies, the MC is bad or the wrong one. I'm running stock D60 1 ton disk setup up front and 3/4 ton (same as 1/2) disks on the rear 60 with the stock MC (TJ). I ran new lines directly from the MC to the axles and after gravity bleeding it stops very well. Can lock up all 4 on pavement with little pressure on the pedal. I do have more pedal travel than I did stock and every once in a while I get the pedal to go to the floor (after sitting for a week) but one pump and it's back to normal. I think after one more bleeding sequence all the air will be out of the system and I'll be set.
Dave