Master Cylinder selection help

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watchdoc

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I have a 71 Dart with 73+ single piston manual disc brakes. It currently has a drum brake master cylinder I believe (equal sized reservoirs but not sure of the bore size). The braking performance is poor.

My plan is to order a NEW 73 disc brake master cylinder in 15/16" bore size. RockAuto and Classic industries list Raybestos MC36406 for around $50.

The 15/16" size is listed as "power disc brakes" and the 1 1/32" is listed as "manual disc brakes". It's my understanding that the 15/16" bore provides more braking performance and a shorter pedal.

So here is the question.

Will the 15/16 Power brake master cylinder work just fine with my manual disc brake dart?
 
More braking power for.....power assist? I vote buy the manual cylinder for manual brakes. The 15/16 quill provide more performance... with power assist...as far as i know.
Dont forget to bench bleed
 
What to think about is volume. A smaller bore cylinder requires more movement to produce the volume needed to apply the pressure. It will have a softer pedal feel because it produces more pressure and you can push the pedal past where it is effective. A larger bore will product more volume with a harder pedal feel when it reaches the required pressure and volume. On a 69 Pro Street Dart I did was a manual brake I ran the 1 1/32" MC.

Food for thought.
 
Also, my single piston calipers have the smaller size pistons. Can't remember the exact size but I'm guessing the smaller size piston could play a part as well.
 
I have tried both of the sizes you've listed and 1-1/8 as well. All were run manually with 73-75 A body discs. I'm currently running a 1-1/32 aluminum MC.
Out of the 3 I've tried on the same car with the same brakes, I prefer the smaller one because it felt best. I plumbed in an adjustable Wilwood proportioning valve in the rear line too.
 
Yes smaller bore = easier pedal, but more travel. I used 7/8" bore from 95-99 Breeze/Cirrus/Stratus w/ adapter plate, for both my manual and power cars. Check Dr Diff for alum ~85 Dodge truck MC but w/ smaller bore (~$100).

People get confused by "why does power MC list smaller bore?". Consider the lever ratio in the stand-off brackets and you might figure that out.
 
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