Vacuum Brakes

[Bruce]

You need to get the Vac Booster, brake pedal, and pushrod. It's all rather simple, just use all the parts mentioned. You might want to take the Dr side seat out to get to the 4, nuts that hold the PM adapter to the firewall. To some it's easier to take the one *hiden* bolt out and remove the pedal holder to take it out to swap the brake pedal over. If you're using a new master cylinder, be sure it's bench bled first. And while you're at it, you might as well bleed enough fluid thur the system to flush all the old stuff out.

For the average guy, just about any brake master cylinder will work. But, there are several choices, of those that are about right.

The PM master cylinder uses 1.25" piston bores for the Master Cylinder.
85-87 Regals (N/A) Master Cylinders use a 24x36mm set of bores.
84-89 F-Bodies (Disc/ Drum) use a 24x31mm set of bores.

The 84 Regals, Vin9 use, a 1 1/16" piston bore for the master cylinder.
Which is most like the PN since both bores are the same.

I've in the past bought Master Cylinders, that in fact the wrong bore combo's for the M/C they were supposed to be replacing. So, IMO, it pays to take a set of calipers, and make sure you get the 1.0625" Master Cylinder.

[DCEPTCN]

Be prepared to be upside-down under your dash for an hour or so- all the blood running to your head and your forearms burning from working upward forever.....and have somebody help you watch while you tighten the four primary mounting bolts, as I pinched my cruise control line unwittingly.

[bob]

For reference, here's the GM part numbers for everything but the discontinued pedal assembly. These were ordered for an 87 NA regal, with what I believe is the 36mm master cylinder. I do not have the part numbers for any other master cylinder combos. Be prepared to pay dearly if you choose to buy all new parts for your pride and joy.

Master cylinder: 18013429
Booster (comes with check valve): 18060040
check valve: 18021981
Booster to firewall gasket: 09791640

bob

[bob]

Something I noticed. The check valve that came with the new booster (black in color) will pass air through in the WRONG direction if you blow on it gentle enough. The one I ordered seperate, in the post above, is gray in color and WILL NOT pass air through in the wrong direction. Watching my vac/boost gauge while going down the highway, I think the slow sweep while going up and down hills could cause the booster to lose some vac under the right circumstances, if you use the wrong valve.
Of course, there's always the possibility that my new valve was bad, but it worked "most of the time".

Oh one other thing, you need to use the washers and retaining clip from the donor car also. The ones that hold the booster arm on the pedal. The pin size is different. I found it easier to remove the whole assembly from under the dash, since pretty much everything needs to come off of it anyway. Don't powdercoat the pin part of the pedal, or you'll have to sand it off in the car. OOPS! :albert: