Just finished off a disc conversion using..

10.9 inch rotors - new
72 ebody pin calipers - new
72 ebody spindles (w/bearing adaper) - new
1 1/32 master - new
all new lines and hoses

10 * 1/3/4 drums out back, not new but in great shape.

no combination or proportioning valve.

Brakes just suck - low but hard pedal and I gotta stand on it to stop the car..

Brakes are bled I guess - no spongy but low and hard as hell pedal.

I know a combination valve is in order but will that fix the feel of the brakes? - which year/body valve should i get? Will a generic under master cyl gm unit work?

I guess I need a residual pressure valve in the rear lines as well - will that fix the pedal height?

What steps should I take to resolve this - I don't want to just throw a bunch more variables into this system and never get it right..

Thanks
Plaz