What is the standard Vacuum Pressure at Booster for 71 cuda?

[wantone]

I just replaced the booster and master cylinder on my cuda.   Measured the vacuum pressure at the booster and it was only 18.   Is this correct?   The brakes feel like they're reliable but very very unimpressive.

I have a front disc and rear drum setup.   

I did not replace the proportioning valve... which is actually not even bolted down... It's just floating in the steel lines.

Ideas?   

Do proportioning valves come pre-set?

[roadman5312]

     18 inches is excellent. But its not a pressure, it's a suction.  Unimpressive in what respect. ?

[wantone]

Unimpressive - as related to how I imagined the car would feel given the old set-up weeped brake fluid out of the master cylinder and wouldn't even get close to stopping w/o full brake pressure.   Plus - I had a frozen star adjuster on the RR.

I'm beginning to think that the rear drum brake cylinders aren't moving freely enough (barely moved when I was looking at them with the drum off)  or proportioning valve isn't working as well as it should.

Thoughts???

[roadman5312]

      Did you bench bleed the new master ? This is a must.  Did you flush the entire system then bleed ?  Any rust in fluid from calipers or wheel cylinders ? If so, rebuild or replace them.  Is the prop valve correct for disc/drum, or an original drum/drum unit ?

[wantone]

I'll try to get a pic of the valve tonight.

As for bench bleed - I did it until i had no more air coming out.  Took 20 minutes of 1/8" pumps until no air with small 10 second pauses in between...and swigs of beer.

Got all clean fluid in now.   That said - the old fluid was brown and gross.

[1 Wild R/T]

While your snapping photos take a photo of the booster/master cylinder....

[roadman5312]

I'll try to get a pic of the valve tonight.

As for bench bleed - I did it until i had no more air coming out.  Took 20 minutes of 1/8" pumps until no air with small 10 second pauses in between...and swigs of beer.

Got all clean fluid in now.   That said - the old fluid was brown and gross.

                      Thank God for the beer     If the fluid was that bad your rear wheel cylinders are probably rusted, maybe calipers to. Make sure get a pic for Wild, I wouldn't know how to id the prop valve.   

[wantone]

You bet - i'm on it.

[wantone]

Here it is

[wantone]

While your snapping photos take a photo of the booster/master cylinder....

I've since replaced with a Cardone/A1 Booster and MC

[wantone]

                      Thank God for the beer     If the fluid was that bad your rear wheel cylinders are probably rusted, maybe calipers to. Make sure get a pic for Wild, I wouldn't know how to id the prop valve.   

Got this done above^   2 cents???

[Chryco Psycho]

looks factory to me