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Old 04-17-2020, 11:31 PM
Tinindianworkshop's Avatar
Tinindianworkshop Tinindianworkshop is offline
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Default Master cylinder

What Master cylinder can I use to replace original single cylinder and conv. To dual master for all drum brakes thanks Geoff

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Old 04-18-2020, 12:11 PM
Doug Doug is offline
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Geoff,
Do a search for "master cylinder" in this forum. A couple of "inexpensive" two-stage units mentioned are the 1980ish Ford Fairmont unit and the 68-74 AMC unit. Apparently, the Fairmont unit is for a front disc-rear drum setup and the AMC unit is 4-drum setup. Both units have the line outlets toward the motor.

Both units probably need pushrod lengthening. You may need a proportioning valve to "balance" front-to-rear braking. A manual valve in the rear line circuit may suffice. It appears that the dual-stage unit reservoirs are sized for front circuit and rear circuit respectively.

Assuming you are working on a "stock" car with original drums, and it is not driven excessively hard and with limited mileage, I would suggest that you keep the single stage unit, having it rebuilt with bronze bore liner by White Post Restoration or some other shop.

Good luck!

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Old 04-17-2021, 04:20 PM
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tallrandyb tallrandyb is offline
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Doug,

I'm converting 65 GTO to dual master cylinder also, but solely for safety sake as I will continue driving this car quite a bit. Single chamber masters result in all brakes failing when one line/wheel cylinder fails, where dual chamber systems retains either front or rear brakes in that situation, enough to likely get you home or at least to the side of the road. What are your thoughts on that?

I just ordered the dual master cylinder conversion kit from Ames (R129TX) along with the conversion lines kit (R180GU), it has all the parts for either 4-wheel drum or 4-wheel disk setups, and you just toss/resell the proportioning block/lines/etc. if you have stock 4-wheel drums since you don't need those parts.

I'm working on my installation now.

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Old 04-17-2021, 08:42 PM
TransaxleTempest62 TransaxleTempest62 is offline
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Quote:
Originally Posted by Tinindianworkshop View Post
What Master cylinder can I use to replace original single cylinder and conv. To dual master for all drum brakes thanks Geoff
I use a 68 to 74 AMC Gremlin master cylinder for manual drum brakes all around.. They also used a disc/drum master on those cars in case you want to do a disc brake conversion later on. You will have to put reducers on the line inlet for the master cylinder since the Gremlin uses larger lines. I got the reducers at Napa. The lines are on the passenger side too. You will have to extend the rod from the brake pedal to the master cylinder. I bought a 3 foot length of threaded rod and cut it down then rounded one end down to fit into the MC. (I am sure there are other ways) I believe the total length needed is 7 1/4 inches long.

There was an article in the Little Indians newsletter in the late 90's or early 2000's that I followed.
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