Front Disc/Rear Drum

I've converted three to front disc & yet to use a proportioning valve. Years back I converted a '69 Ranchero, more recently my Comet, latest my '69 Fairlane. I did use a disc/drum master cylinder on the Comet. On Ranchero & Fairlane disabled the residual pressure valve in MC for front drums. None have/had power brakes and have approx equal brake bias. I suspect with power brakes there may be a tendency to lock rears first, but with manual, need to be on brakes very hard before lockup occurs.

I was planning on a full conversion of Fairlane, but last year the 54 year old booster on Cobra finally gave up, installed one earmarked for Fairlane on it.

 

I have been running the orginal '71 drum/drum master cylindar since the conversion and I have had no issues. It does take a bit more effort to stop but not a huge issue. It also is not locking up the rear even under very hard braking. I am hoping to get the '74 disk/drum master cylindar installed this week.

 

Good idea on the '74 disc/drum master cylinder. I'm running a '75, but with the '74, you have to re-flare the end of only one of the short lines that go from the MC to the distribution block. the other one is already the correct fitting size.
Save the push-rod from your old drum/drum master cylinder and install it on the new disc/drum unit, because the push-rod that comes with the disc/drum MC is longer which will cause your brake pedal to be uncomfortably high...

 

Hey everyone, I really appreciate the replies... I have been super busy the last several weeks with high school finals and other similar bs but I am excited to start tackling the brake conversion once again!

 

Thank you for the advice. I do have a question how do you remove the push-rod from the MC. It seems to clip in and once installed it will not come out.

 

Place the old MC in a vice, put a large adjustable wrench over the "eyelet" end sideways. Smack the wrench with a large hammer. The clip will break and the push-rod will come out. The new MC has a new clip in it, and normally comes with the push-rod not installed. Snap your old push-rod into the new MC and make sure it locks in place...

 

Finally got the master cylinder installed. Ended up removing the line for the rear brakes and replacing both fittings. It seems the fitting that connected the line to the distribution block was damaged at some point and it may also have damaged the block too. I had a hell of a time getting the line to seat and seal. If it leaks again I may have to replace the block. If I do does anyone have a recordation on one to use? Maybe from a Mustang or other Ford that is available.

 

Looks good. Why are you using fitting adapters? Did you paint the calipers?...

 

I did not paint the calipers, that is how they showed up.

On the '74 master cylinder it comes with the adapter for the front brakes and the line fit the adapter without changing the fitting. On the rear brakes I had to change the fittings on the line and could not find a 7/16 x 24 fitting localy but did find two 1/2 x 20 fittings and I already had the 7/16 x 24 male to 1/2 x 20 female adapter on hand so I used it.

 

Those calipers & hubs are gonna get all rusty. Should have sprayed high-temp paint on them. Might be able to do some masking and paint them while they're on there.

Should look like this:

 

After a couple of aftermarket block failures, I ended up getting a OEM for a 70 - 73 Mustang disc/drum car and rebuilding/resealing it. After installing the OEM, I found out the problem with aftermarket blocks is that one of the seals is incorrect, and will fail. If you use aftermarket get a seal kit for an OEM and use those seals instead, all should be good then.

 

Thank you for the advice