[Mario64]

Hi all:
I'm new to this car and I want to keep the power drum brakes but not the single circuit master cylinder. What dual circuit master cylinder will work with the factory booster and drums?
Thanks all,
Mario64

[Stuart]

I think in general people use a dual master cylinder from a 1967-1969 full size Pontiac, but there are others that may work. Here is an old discussion about that conversion: https://forums.maxperformanceinc.com...d.php?t=641491

[hurryinhoosier62]

Originally Posted by Stuart

I think in general people use a dual master cylinder from a 1967-1969 full size Pontiac, but there are others that may work. Here is an old discussion about that conversion: https://forums.maxperformanceinc.com...d.php?t=641491

Stuart, I discussed this with Nunzi over ten years ago. IF I remember correctly the dual master cut from the 1970 “B” bodies with drum brakes could be used as well.

[tom s]

I hope what ever you do does well.Have a couple friends that have done them and were very dissatisfied with results and took some major effort to get resolved.I have just stayed with the single because of it.Tom

[Mario64]

I want to thank all of you that took the time to reply.
I have installed the scarebird conversion on my buddy's 66 Olds. That used front discs and a Buick wagon disc/drum master. I ran the lines like mentioned in the first post. Front port to the line to the distribution block. Then on to the front brakes and a barrel connector from the rear port to the rear brakes. That was my second scarebird kit. The first one on my 68 Deville. I used a 9" booster and a vette style master. Both operate flawlessly.
My question stems from a drum/drum install, unlike the other which were disc/drum.
I will post results when done, probably a few weekends.
Thanks again.
Mario64

[Goatracer1]

I used a master from a 1967 full size Pontiac on my 1964 GP. It work well with no problems.

[tom s]

To be clear,the 2 cars that had issue were 8 lug cars and were only changed to a dual master,no brake changes at all.Tom

[Mario64]

Originally Posted by tom s

To be clear,the 2 cars that had issue were 8 lug cars and were only changed to a dual master,no brake changes at all.Tom

hi tom:
that is an interesting observation. are the two cars you are referencing manual or power brakes?
and why would it make a difference between the five lug drums or the eight lug drums?
thank you.
mario64

[tom s]

They were both power brakes.Not sure if the 8 lugs had anything to do with it.Just wanted to make it clear there was no brake changes like going to disc somewhere.Tom

[Mario64]

Thank you. Will update when brake job is complete.
Mario64

[stevep]

I would use a mid 60s Cadillac master as the outlets are on the other side, which makes it easier to plumb it.

[Mario64]

Originally Posted by stevep

I would use a mid 60s Cadillac master as the outlets are on the other side, which makes it easier to plumb it.

Thanks Steve for that tip. I just picked up one for a 66 Deville. I will check back when install is done.
Mario64

[Richie Hoffman]

Master power brakes makes a booster master combo works perfect in those cars