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Discussion Starter #1 (Edited)
Did a quick search and couldn't find a straight answer...

going to run manual brakes on my 63.

Discs in the front
drums in the rear (for now)

What size bore?

7/8", 1", or 1 1/8"

from what i have read 1" should work right, correct?

Thanks
-theo
 

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Discussion Starter #3

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Thanks awsome info.

So what do you think? it is a street car so i don't want a hard pedal should i just run a 7/8" bore?

I don't have any experience to tell me what kind of setup I would prefer, but i just don't want to have to stand on the pedal at stop lights.
Mine is different with manual 4 wheel disc brakes. So I am no help.
I have the complete system from MP-Brakes.

AL
 

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Discussion Starter #5
Mine is different with manual 4 wheel disc brakes. So I am no help.
I have the complete system from MP-Brakes.

AL
Well rear discs are coming...not sure if the car will get on the road before i collect enough cash to purchase the brakes. If i finish rebuilding the motor first then it will be on the road with rear drums for a month or two before i buy the rear discs.

Is it a manual setup? how does the pedal feel? and what size bore?

Trying not to have to do things twice...but I will if I have to:D
 

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Well rear discs are coming...not sure if the car will get on the road before i collect enough cash to purchase the brakes. If i finish rebuilding the motor first then it will be on the road with rear drums for a month or two before i buy the rear discs.

Is it a manual setup? how does the pedal feel? and what size bore?

Trying not to have to do things twice...but I will if I have to:D
Mine is 1''

Same used in a 69 Corvette Manual brakes.
 

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With a manual disc/drum setup you want to run a 1" or 15/16" bore MC. What front caliper setup do you have? The ratio of MC bore to caliper piston bore is what matters for pedal effort. MP brakes neglects to mention this (along with Pascals law). You also need a combination valve for a disc/drum setup. You can but a MC with the valve in one shot. CPP has them (along with others): www.classicperform.com.

With a manual disc/disc setup the MC bore size should be close to the same, depending on what calipers you run. This setup only requires a proportioning valve (adjustable or pre-set).
 

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I am using the 68 vette manual disc master with the 1 inch bore. Works great with the non power disc drum set-up and I have not needed a prop valve.

I went non power for 3 reasons, my motor makes next to no vacuum, I dont like the way a booster looks, and I saved about 15 pounds that way.
 

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while were on this subject, i have manual disc/ drum( 9" ford drums if it matters) with the Heidts front clip with their manual mc and combination valve for d/d.
my pedal travels almost to the floor before stopping , is the mc size not correct for the 9" ford drums or what, the brakes just dont seem right.

thanks for you comments, roger
 

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I am using the 68 vette manual disc master with the 1 inch bore. Works great with the non power disc drum set-up and I have not needed a prop valve.

I went non power for 3 reasons, my motor makes next to no vacuum, I dont like the way a booster looks, and I saved about 15 pounds that way.
The combo valve for disc/drum includes a metering valve and a prop valve in one. The metering valve momentarily sends pressure to the rear brakes before the fronts to take up slack between the shoes and drums. The prop valve limits the pressure going to the rear brakes because of load distribution during braking. Without this valve the front brakes are going to wear faster and possibly overheat during normal driving, and during a hard stop your rear brakes will likely lock up first and send the car spinning.

Most of us are real easy on our cars so these things may not be noticable, but IMO they are necessary.:yes:

while were on this subject, i have manual disc/ drum( 9" ford drums if it matters) with the Heidts front clip with their manual mc and combination valve for d/d.
my pedal travels almost to the floor before stopping , is the mc size not correct for the 9" ford drums or what, the brakes just dont seem right.

thanks for you comments, roger
I would first check your MC pedal rod and make sure you only have 1/4" play or so.

If you pump the pedal fast and the pedal pumps up and gets harder then you have air in the system.

A MC bore that is too small can increase your pedal travel too much as well. Are the brakes real touchy when they start to grab? What is the bore size?
 

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Re brakes

DENFINTLY MAKE SURE THE MC ROD IS ADJUSTED A COUPLE OF TURNS IS THE DIFFERENCE OF BRAKES AND NOT I JUST PUT WILLWOODS ALTHE WAY AROUND ON MY NOVA I JUST HAVE AN AJUSTABLE PORPORTIONING VALVE ON THE ON THE REAR ACORDING TO WILWOOD THATS ALL YOU NEED IVE ALSO HAD SEVERAL OTHER CARS WITH FRONT DISC AND DRUM NEVER USED A COMBO VALVE ALL WORKED FINE :yes::yes::yes::yes:
 

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nogo/d64nova

i got bout 1/8" play in rod
if i pump brakes fast it just stays the same ( low pedal) dont come up
brakes are normal when stopping not touchy.
1" bore manual m/c from heidts w/ their disc/drum combination valve.

i was wondering if the 9" ford wheel cyls. had anything to do with it ?


thanks , theracer
 

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just tyin' to check to see if there was something i could do to make them better, and not something wrong or out of balance with the system.
just thought i ought to have a better pedal.

i'll check again, tonight about the rod length as you mentioned.

theracer
 

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i there anyway to tell if you have a disc/drum combination valve
or a disc/disc combination valve ?

thanks, theracer
 

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The combo valve for disc/drum includes a metering valve and a prop valve in one. The metering valve momentarily sends pressure to the rear brakes before the fronts to take up slack between the shoes and drums. The prop valve limits the pressure going to the rear brakes because of load distribution during braking. Without this valve the front brakes are going to wear faster and possibly overheat during normal driving, and during a hard stop your rear brakes will likely lock up first and send the car spinning.

Most of us are real easy on our cars so these things may not be noticable, but IMO they are necessary.:yes:



I would first check your MC pedal rod and make sure you only have 1/4" play or so.

If you pump the pedal fast and the pedal pumps up and gets harder then you have air in the system.

A MC bore that is too small can increase your pedal travel too much as well. Are the brakes real touchy when they start to grab? What is the bore size?


I'll post some results after i make some 125-130mph passes @ the track next week...
 
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