Master cylinder question

[Coleydog]

I have a 15/16 and a 1-1/16 bore MC, whitch one will give the softest pedal effort? I had heard this before but can't remember.
Mike

[kansas stocker]

15/16

[Coleydog]

Thank you

[FireSale]

You need to match the piston area of your calipers to the bore of your MC to get the best stopping power. Smaller bore give higher pressure if the pedal ratio is right.


Joe's Racing has a good article on Master cylinder math. Link below.


https://www.joesracing.com/rt-4172-m...nder-math.html

[GTX JOHN]

15/16 on all our stockers........

Most of our cars are 4 Wheel Aftermarket Discs.

[Coleydog]

Pulled the snap ring from bore, saw its 1" just like the factory cylinder on a 70 Duster. New aluminum two bolt like factory, has the groove for rod lock. Bought at Carlilse in a box of parts, mc adapter, coil overs, a-arms, heim joints, proportioning valve and 10 lb residual valve, many misc parts, all for $100, all new. I'm using Strange disc on front, drums on back.
Thanks for replys
Mike

[GTX JOHN]

Try it.....It will probably be fine.

It is a little subjective as different folks like
a different petal feel.

[FireSale]

I guess I'm an odd bird. When I was driving my Mustang to the track it had power brakes and I liked the ease of staging and always hitting the first turn off. When I put it on a trailer and went to manual brakes I never adapted to the feel. Now I'm back to power with a Strange master, a vacuum pump and reservoir tank. Much more comfortable with the way the car responds.


Note: I'm 71 and don't have the leg for it any more...

[L78 Nova]

With all other aspects the same...
a smaller MC bore will require more stroke with less effort to reach equal braking pressure (providing the volume is still adequate).


a larger bore MC will require less stroke with more effort to reach equal braking pressure (larger is required when caliper volumes are greater)


Larger- multi piston style calipers "generally" have more piston area so they will provide more brake application force at lower pressures. ie. they work in conjunction with the larger bore MC.

[Eman]

Originally Posted by Coleydog

Pulled the snap ring from bore, saw its 1" just like the factory cylinder on a 70 Duster. New aluminum two bolt like factory, has the groove for rod lock. Bought at Carlilse in a box of parts, mc adapter, coil overs, a-arms, heim joints, proportioning valve and 10 lb residual valve, many misc parts, all for $100, all new. I'm using Strange disc on front, drums on back.
Thanks for replys
Mike

Your call but I don't think you'll need a proportioning valve or a residual check valve, every car is different. I've got GM Metric calipers on the frt. and drum on the back with an aluminum Mopar MC 1 1/16 bore with no ck valve and I have an adjustable prop valve but it's wide open.
What works for me footbraking is the largest bore rear wheel cyls and secondary shoes in both positions for more friction surface area.