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Discussion Starter #1
I'm putting 4 wheel disc brakes on the 66 coupe. I have an adjustable proportioning valve, but I wonder if I need a special master cylinder. I am planning on using the 67/68 disc brake master cylinder. Any problems? BTW, how do I graduate from "newbie". I haven't been new in years! :) Thanks

Ronny
68 Fastback, 66 Coupe, 64 Ranchero
Mustang Owner's Club of Austin, TX
 

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What type of calipers are you using on the front and rear? I did a four wheel disc mod on my race car using Granada spindles,rotors and calipers up front, and (gulp!) Chevy calipers in the rear. After almost wiping out my car I realized I needed a larger master cylinder to compensate for the extra capacity of the larger calipers. When I had just the Granada stuff up front and drums in the rear it worked fine. But after I added the rear discs I soon realized that more fluid to brakes was needed.

Every day is a holiday if you love your job.

Current projects: 65 Fastback, 68 Coupe Oval Track Racer, 64 Galaxie 500 XL, 54 F-100 Pickup
 

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Discussion Starter #4
I've got 4 piston calipers from Stainless Steel up front and a Versailles rear end. My concern is more with the rears and the disc/drum master cylinder. I have read about some valve in the drum masters that the disc master don't have, but I can't remember the details.

Ronny
68 Fastback, 66 Coupe, 64 Ranchero
Mustang Owner's Club of Austin, TX
 

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Ronny, I have the same setup, using the dual MC and proportioning valve that Stainless provided. Works OK with the Versailles. W/o power it takes some leg to get maximum braking. I wonder if a power unit would make a big difference? It seems that w/ the proportioning valve, if pressure is correct, the system should be OK.
KK

66 Coupe, 351W, C4, 9" Versailles+Auburn
 
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The disc/drum master has a residual pressure valve in the drum brake outlet port. The valve is under the brass tubing seat. You can remove the seat and remove the rubber valve.
I have removed the seat by screwing a small sheet metal screw into it and then pulling it out. You will do some damage to the seat by doing this so be careful to not damage the seat too badly while removing it. While you have the seat out you can carefully smooth out any damage you caused during removal. Reinstall the seat and the master is ok for 4w/ discs usage

Greg B
 
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