Has anyone done that?  Thinking of doing that and would like to call on anyone who has and what problems I could encounter.

I too have the Granada front discs and dual master cylinder which I did 10 years ago. I'm not 100 % happy with that setup as I've had to make a few panic stops and thought car should have stopped sooner in that situation. I find that I have to pump the brakes  to get a good firm hard stop. Of course , in a panic situation I don't have that luxury.  I keep going back to Gil Baumgartner's comment where he stated to me in an email that disc brakes need approx. 1200 psi to be fully effective.

It sounds more likely you have a mis-match of parts and/or incorrect adjustment/system bleeding. That line pressure is generated by caliper style/piston size chosen, MC type, pedal ratio and amount of pressure you can put on the pedal. Power assist only makes it easier to achieve that brake line pressure. Factory cars also came through with manual disc/drum.

You have a GRANADA disc swap on your BIRD now? What size wheels?

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I agree, pedal ratio makes a big difference. 6 to 1 and a MC of 7/8” or smaller normally do not need a booster. I remember my dads new 55 sunliner he had the dealer add a Bendix booster. It was a lot more sensitive than the 56 Victoria which he didn’t add one.
When I changed rear ends in my 56 the brakes came off a vehicle with power brakes and I changed the wheel cylinders to a smaller size. Also 4 piston or 6 piston calipers seem to work fine without one. There are a lot of options and opinions.

56 Vic, B'Ville 200 MPH Club Member, So Cal.

14" wheels

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