cudak888
Well-Known Member
Hello all:
In good old "there goes the aftermarket" fashion, the relatively new 8" dual diaphragm Pirate Jack booster that I installed on my '68 Satellite bit the dust last weekend - it's sucking manifold vacuum through the rear seal. Brake feel is about 75% of what it used to be.
For the record, this is the setup. The car used to be drum/drum, but if you have to think of my question in terms of the overall setup, just think of it as a factory disc/drum car now. All of the correct parts are there - firewall plate, Z-bar, hold off valve.
Also note that the PJ master cylinder was junk as well (wouldn't bench bleed correctly), so I'm running an appropriate Cardone unit instead:
Since there's been no reply from PJ (none from when I inquired about a very minor hiss at the back of the booster months before it failed entirely) and I don't expect anything else out of them, I'm studying my options.
I know the PJ booster is also sold by a few other distributors (for $250 - $300 clams!), and frankly, I'm not interested in anything that looks like it's the same thing that failed quick on me before.
I know there are the oddball wannabe Hemi-type boosters mounted on risers out there, but I'm rather interested in the idea of something that A. Isn't priced ridiculously and B. Could be had at a parts store. So I've been snooping around on Rock Auto looking for interesting fixes. Interesting in terms of "it's cheap" and "Hey, look, I found a workable combination that nobody thought of yet."
Thus, I've been wondering whether a simple 1976+ B-body single-diaphragm booster like this one would work, but there's two things I don't know: Is the firewall bolt pattern the same as the pre-1974 cars? And if it is, is the diameter larger than 8"? I know one of the limiting factors on the '68 is the inner apron.
The way I see it, single-diaphragm shouldn't be an issue; after all, I'm running the same 11.75" brakes up front as an M-body, which had a very similar booster (far as I can see, the major difference is the more common two MC studs vs. the Mopar four). I also have the PJ bellcrank already installed, so I've got that end sorted - but there's the issue of whether the rod at the back of the booster is big enough...
I've also considered this from an '80 Newport (R-body), which uses the two-bolt master type - but I have a few Ford masters kicking around which I could probably adapt.
Any advice?
-Kurt
In good old "there goes the aftermarket" fashion, the relatively new 8" dual diaphragm Pirate Jack booster that I installed on my '68 Satellite bit the dust last weekend - it's sucking manifold vacuum through the rear seal. Brake feel is about 75% of what it used to be.
For the record, this is the setup. The car used to be drum/drum, but if you have to think of my question in terms of the overall setup, just think of it as a factory disc/drum car now. All of the correct parts are there - firewall plate, Z-bar, hold off valve.
Also note that the PJ master cylinder was junk as well (wouldn't bench bleed correctly), so I'm running an appropriate Cardone unit instead:
Since there's been no reply from PJ (none from when I inquired about a very minor hiss at the back of the booster months before it failed entirely) and I don't expect anything else out of them, I'm studying my options.
I know the PJ booster is also sold by a few other distributors (for $250 - $300 clams!), and frankly, I'm not interested in anything that looks like it's the same thing that failed quick on me before.
I know there are the oddball wannabe Hemi-type boosters mounted on risers out there, but I'm rather interested in the idea of something that A. Isn't priced ridiculously and B. Could be had at a parts store. So I've been snooping around on Rock Auto looking for interesting fixes. Interesting in terms of "it's cheap" and "Hey, look, I found a workable combination that nobody thought of yet."
Thus, I've been wondering whether a simple 1976+ B-body single-diaphragm booster like this one would work, but there's two things I don't know: Is the firewall bolt pattern the same as the pre-1974 cars? And if it is, is the diameter larger than 8"? I know one of the limiting factors on the '68 is the inner apron.
The way I see it, single-diaphragm shouldn't be an issue; after all, I'm running the same 11.75" brakes up front as an M-body, which had a very similar booster (far as I can see, the major difference is the more common two MC studs vs. the Mopar four). I also have the PJ bellcrank already installed, so I've got that end sorted - but there's the issue of whether the rod at the back of the booster is big enough...
I've also considered this from an '80 Newport (R-body), which uses the two-bolt master type - but I have a few Ford masters kicking around which I could probably adapt.
Any advice?
-Kurt
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