Informal poll - 1948-52 F-1 Front Disc Kit

[V8 Bob]

Originally Posted by 1948F-1Pickup

I've been using the 1" master with the drums for 5 years and it's good...
I would say the increase in pedal movement toward the floor is very slight
when compared to the pedal you experience with the original 1 1/16" bore master. Personally, I wouldn't go down further in bore size to a 7/8" though.

The 1" Mustang master I'm using is for 4 wheel drum manual brake application. It has the residual valves in both ports. There's a chance it will operate and do the job just fine with the residual valve in place. The height of the master and the height of the caliper are pretty close.... close enough that you probably want some residual fluid control in the line to the front brakes. Whether the 1" master's residual valve provides too much pressure on the calipers is the question. That I will determine.

The early style K/H calipers will work OK, but modern aluminum 4-piston designs would be a better choice, imo.

I agree with not going any smaller than a 1" master, but simply using a disc/drum master cylinder would solve the residual issue, and provide safer and correct disc fluid reservoir volume.

If you are "intent" on using the drum drum master, use an easy-out to pull the disc axle tube seat, remove the residual assembly and reinstall the seat. The drum brake residuals should not be used on disc brakes!