I did a drum to disc conversion on my 64 impala front end. 327 car, power glide trans. Dual mastercyl,new lines to the front. Problem is when I touch the pedal, the brakes lock up very easily. Have to be easy on the pedal and if it's to firm she locks em up. Any way of adjusting the brakes?I'm still learning as I go.
What master cylinder did you use, your need one for disc brakes. I'm guessing disc / drum and not 4 wheel disc.
More details needed, ie, do fronts only lock up or all, or rear only ? As post 2 also, Proportioning valve may help, or may have to adjust rear brakes
Yes it is disc drum setup with proportioning valve. It's a dual Mc. Not sure of the name brand. Kit was from mcgaugheys
Do you have the lines hooked to the proper ports on the mc?...usually on disc - drum mc the disc portion has a larger reservoir but it can be in the rear of the mc and thus cause confusion...
My suspicion is it's plumbed backwards somewhere; either between the master and the proportioning valve or between the valve and the brakes. Like as said above, there's front/rear ports on these and it makes a difference...
Definitely talk to whoever you bought the kit from first. Are they power brakes, is the proportioning valve adjustable?
They are power brakes. Don't believe the prop valve is adjustable. It feels like the fronts are locking up. Haven't driven in a while.
Usually the rear brakes tend to lock up on disc conversions. Back to what Clem suggested, how is the rear brake adjustment?
Power brakes, were they manual before and did you move the rod to the other hole in the peddle. '64 Impala came with standard and power brakes and as I recall there were two holes in the brake peddle for the actuater rod, that is because it takes less peddle pressure for power brakes and Chevy used a different peddle ratio to allow for the difference. If all 4 brakes are locking up you are just pushing too hard. There is no adjustment on the front brakes at all, you bleed 'em you run 'em.if you are coming from a late model car to this heap there is one thing to remember, there is nothing to keep you from locking the brakes up, there is no anti-lock brake setup. You have to learn to feather the brakes, that is how we drove these old heaps when they were still late model.
It was always power brakes. I'll check and see if there is another hole on the pedal. I don't believe there to be one. The rears are adjusted to drag, then backed off .
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