I already have bought a 68 mustang drum brake M/S to do the dual circuit conversion on my 64 F100. I eventualy intend to install a disc brake swap from speedway motors but will have to wait.

I intend to keep the manual brakes as with discs have always found them to be sufficent in braking ability however being like most people I will install easy if I can.

This is the gig,

The 68 mustang M/S uses a 1" bore. I got currious as to availability of an aluminium M/S to keep that nasty brake fluid rust at bay. So I went to wilwoods site and noticed a 7/8" bore M/S. This uses the same patteren as the mustang piece and offers a smaller bore which according to pascals law should give me the same pressure with less effort.
I think on a drum/drum setup this would deliver ample fluid volume with only slightly greater pedal throw. But, will a 7/8" M/S have sufficent volume to pump a 2.9" caliper piston shut?

I posted this in the "brakes" forum and the only response I got was a go with the 7/8" for ease of use. Nothing realy on whether or not it will be capable of sufficent volume.

I figure dual circuit brake conversions are more common here and in the 50s forum.

Anyone gone this road?