Dual Master cyl.-?

I am planning to replace my dual master cyl. that I put on my 59 20+ yrs. ago, I think it was for a AMC Ambassador, not 100% sure, I was wondering if anyone has come up with a better unit over the years. I have the power brake set up under the dash, where can I get a rebuild kit for it, I did it about 20+ yrs. ago also. Thanks, Wayne, in Fl.

Use a master for a 1967/68 cadillac fleetwood w/4 wheel drum brakes. You will need to reroute the brake lines as the caddy lines come out on the fender side instead of the engine side like the amc cyl. Also, the caddy cyl. Is a larger bore giving more pressure and faster brake response. Hope this helps.
Bill

Thanks Bill, I'm on the fence about changing over to disc, I may try this 1st., thanks, Wayne

Almost any early dual cylinder Ford Master cylinder will work and lines go in on the fender side.
When I need one I just go to Auto Zone and tell them I need a master Cylinder for a 1968 Mustang, you can get a drum/drum or disc/drum one. You want the small bore 1" unless you have power brakes.

Thanks Ford Only, it has power brakes, BUT it does not seem to really help much, not like the 70's Fords. You say the smaller bore 1", I was thinking, the bigger the bore the better, is that correct,-?, thanks again, Wayne in Fl.

The bigger bore increases line pressure thereby giving a faster response at the wheel cylander. That is the reason i changed from the amc master to the cadillac unit. The bendix power unit used in 56-59 only decreased foot pressure to the master. It did not increase brake actuation and response. Hope this helps.
Bill

I have used both the 1" bore and the 1-1/8" bore with a power booster and never really felt much difference. You can Google the question and get more answers, in short the smaller the bore the less foot pressure its going to take to stop.
On you thoughts about disc brake conversion, I would not do it unless you are going to run radial tires. The stock drum brakes will lock up the original size bias ply tires, disc brakes will only lock them up faster. I converted a 60 Thunderbird and a 59 Skyliner to disc brakes and I find that it is very easy to lock the wheels up with the 8.00 x 14 bias ply tires. I used radials on the Skyliner for awhile and it stopped great but I kept having problems with the tires so I went back to the bias ply tires.

Thanks Bill, so that is why it never really felt like power brakes!!!!, I went thru everything on the brakes back when I restored the car and when I drove
it for the 1st. time, I thought the brakes really SUCKED, LOL, so the bigger booster that goes under the hood would be much better. Thanks, Wayne

Thanks for the reply Ford Only, I did have radials for about 10 yrs., but then put on the wide whites, 800 x 14, but I never have been able to lock up ANY of the wheels, when I restored the car, I put on new everything, wheel cyl's, drums, shoes, lines, AMC dual master cyl, rebuilt the power unit under the dash and the brakes were never that good. I'm near Tampa, Fl. and I have to get on some major hwy's here a lot and I just go with the flow, 60-70MPH, it takes ALOT to get the Ford to stop!!!!!! I have been looking around, it seems that a 10" disc will work OK, not 100% sure yet, I will do a test fit with one of my wheels next week. There is 1 show I go to weekly, 3 lane, about 15 traffic lights about 1/2 mile apart, I think the disc would be much better for that kind of traffic, thanks, Wayne, if I get the disc to work, I'll post it!!!!

Does anyone know what model, year-?, brake booster will fit under the hood, I will be running 10" disc up front with the orig. stock 14" wheels, I will be taking out the bellows assy. under the dash. I will be taking a lot of pic's and will have part #'s if any one wants to know more about my set up with the stock wheels, thanks for ALL the reply's, I read them all, NEVER to old to learn!!!!!, Wayne, sunny, Fl.

This is one that's on E-bay http://www.ebay.com/itm/1957-1958-19...p2054897.l4275
I don't think you will be able to use the stock wheels without a spacer but if it works let us know as I have a couple more Fords that I may ad disc brakes to in the future.

Thanks, Ford Only, I test fit the disc today, it clears OK, using the stock front hub, the studs may be to short, I did not put the wheel on it yet.
I had the hub & the 10" disc on the bench for a test fit, looked good, I will need to make a bracket to hold the caliper, I'll post the results, thanks, Wayne

Google Master Power, LLC in Mooresville, NC. Their business is drum/disc brake conversion kits. They can help you. I just upgraded the drum brakes on my '59 to a duel booster system for safety reasons. They supplied everything I needed and it was a straight bolt on conversion.

Thanks Ron, I'll do that, did you go with disc brakes-?, Wayne

Wayne,
No, I still have drums all around. Original under the hood booster and master cylinder both needed rebuilding, so I opted to change to the dual master cylinder system for a safer braking system.

Thanks, Ron, I did find & saved there site, I have a disc brake & caliper that I'm going to put on the front, working on a rear disc also, so far it looks like the stock 14" wheels will work, I'll post the results, thanks, Wayne

There is a new rebuild kit for the Kelsey-Hayes underdash unit available from most of the usual vendors now.
The P/B master cyl is 1.125" bore. This set-up stops ok when right.
You can have your shoes relined with softer material for quicker stops.
The bigger bore m/c's move more fluid (for higher line pressure) and are harder to push.

Ron.

I want to add something to this discussion for clarity. A smaller master bore creates a higher hydraulic pressure for the same force applied to the brake pedal.