The 1976 Monza MC you're using should be a straight 7/8" bore...too early to be a quick take-up style. The Monza used small, 11/16" bore rear wheel cylinders. You haven't said what your application is, but if it's the usual 67-69 F-body, those used 7/8" bore wheel cylinders out back, a full 60% more effective area than the Monza units.



Do you have a brake pressure gauge kit? I'd be curious to know what pressures you're getting in the rear with max and min proportioning.

Tobin
KORE3