?? power drum brakes 92 booster 70 master

[fs64]

I have been following multiple power brake threads and went with a 92 booster and a power drum master cyl from a 70 Buick station wagon. The power master cyl piston has a shallow dimple compared to a non powered one but it is slightly deeper than the disc brake master off of the 92. Is this ok?
The second concern is that the ID of the 92 booster opening is = 2 inches and the OD of the 70 master is only = 1.5 inches. They bolt together perfectly and the master cyl flange almost covers the booster recess completely.
Am I good to go or have missed something?

Thank you, Todd

[PGSigns]

I would go with the early model booster to match the master cylinder. When it comes to brakes you want it all 100% working together.
Jimmy

[Captainfab]

If the dimple in the '70 Buick master is slightly deeper, you should be able to take up that difference in the adjustment of the booster pushrod to pedal arm. As with any brake work/upgrade you will want to very carefully test your installation away from traffic until you are confident your brakes are operating correctly.

[BigSix]

I have a 69 master and 82 booster going in my truck now. I did exactly as the captain says. Just a slowly adjusted the rod out until it hit the master cylinder piston. Haven't run it yet because I have to run lines - so I can't tell you if I will hit any snags but so far I *think* I am ok. Our masters are the same but I don't know if the 82 and 92 masters are the same. Either way if you are not 100% on your work its best you do not proceed and have it done so you know its 100%!!!

[Captainfab]

A '69 pickup master will have the deep bore in the back of the piston and a '82 booster will have a short pushrod for a shallow bore (dimple) in the back of the master piston. Those two are not compatable unless you changed the intermediate pushrod.

Originally Posted by BigSix

I have a 69 master and 82 booster going in my truck now. I did exactly as the captain says. Just a slowly adjusted the rod out until it hit the master cylinder piston. Haven't run it yet because I have to run lines - so I can't tell you if I will hit any snags but so far I *think* I am ok. Our masters are the same but I don't know if the 82 and 92 masters are the same. Either way if you are not 100% on your work its best you do not proceed and have it done so you know its 100%!!!

[BigSix]

Originally Posted by Captainfab

A '69 pickup master will have the deep bore in the back of the piston and a '82 booster will have a short pushrod for a shallow bore (dimple) in the back of the master piston. Those two are not compatable unless you changed the intermediate pushrod.

I changed the intermediate pushrod for a longer/adjustable pushrod from the 69.

[RAYDAY]

I used a 2002 caddy boster and a 60's all drum master before on the truck I'm doing now its a 66 Buick master and a 70 Chevrolet boster lots of gm awsome swapability

[BigSix]

Just thought I would update and let you guys know I ended up staying single circuit with a 65 master and 82 booster. 4 wheel power drums are sweeeeet!

I didn't feel like splitting the system with new lines so its staying single circuit for now and I couldn't be happier with the power brakes!

[fs64]

Hey BigSix,
I imagine that for the 65 master to bolt to the 82 booster you would have been faced with my concern over the ID of the booster recess being larger than the OD of the master cyl. It sounds like it did not present a problem for you?

[BigSix]

I didn't notice that issue. Everything fit together as it did when I had a 69master/booster in my possession. I did use the longer and adjustable 69 intermediate shaft.