I love a disc brake conversion.
dual master only. dont fart around with your OEM single-not safe.
on my 52 I did a master only home made setup (back in the 90's) and used a master from Nova(new) that had 1" bore.
used a combination valve from a 76 camaro(same weight and same balance ratio)
5 lug disc conversion on straight axle
loved it and it worked flawlessly.
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on my 52 panel i did a master from 70's chevy truck and booster from 71 ford 3/4t 4x4 which is a 7" dual diapfram booster.
too much boost.
dont do it.-will slam you through windshield. =)
also did the camaro combo valve. not enough juice going to rear brakes-should have found combo from maybe a suburban or wagoneer or something like that with more 50/50 ratio.
never a stopping issue though. EVER! I can out-stop any car i have ever driven.(camaro front clip)
combination valves required on any conversion.
combo valves have proportioning valve which decides how much power goes front or rear and the ratio.
they also have residual check valves which are required for all systems.
discs like about 2# pressure and drums have harder springs and like about 10#.
if you only use proportioning valve(ratio) your pedal will sink low and/or double pump to stop to overcome the springs which have pulled shoes away from drums.
i like to buy from rockauto.com or napa for master/booster so that i have OEM type part number for replacement. CPP is GREAT company but I dont want to have to reply on them for master replace when I need one.
I goto pick/pull for combo valve.
dig around in a NON-ABS car like 1981 and earlier.
just take those dikes and kink/snap brake lines leading to valve which may be mounted by booster or down by frame rail.
I stick with chevy and if a truck any nova/camaro/skylark... will work.
