Which Brake Booster??? Help!!

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MadMaxCustoms

MadMaxCustoms

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I have a 1969 dodge dart. Doing a S6 to V8 Conversion.
Doing a front dist brake conversion and have 10" rear drums. All 4 on 5 bolt pattern.
360 with a 727 behind it.
So,
I want power brakes and need to know which diameter brake booster to buy. I heard the larger 8" boosters are impeded by the valve covers in the engine compartment. True?
I have found some decent deals on ebay but maybe someone has a booster/master combo I can buy?
Also I need a new front proportioning valve. Any ideas/have one I can buy?

New at this and need a little help.
Thanks!!!!!
 
Why do you want power brakes? With a disk/drum A-body a 15/16" manual master cylinder is pretty darn awesome. Better pedal feel, better modulation/control, and really the pedal effort isn't that stiff. I switched my Challenger from power to manual after driving the manual set up on my disk/drum Duster. Maybe an aftermarket booster would be a little different, but the stock power brakes are "overboosted" in my opinion, like the stock power steering. Sure it's easy, but there's no feel.
 
Majority of performance cams wont support a vacuum booster anyway.
 
72bluNblu said:
Why do you want power brakes? With a disk/drum A-body a 15/16" manual master cylinder is pretty darn awesome. Better pedal feel, better modulation/control, and really the pedal effort isn't that stiff. I switched my Challenger from power to manual after driving the manual set up on my disk/drum Duster. Maybe an aftermarket booster would be a little different, but the stock power brakes are "overboosted" in my opinion, like the stock power steering. Sure it's easy, but there's no feel.
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Thank you.
After much research I am going manual. Just need to find the correct master and Ill be good to go. Is a 1" bore to much?

Many thanks for your feedback.
 
MadMaxCustoms said:
Thank you.
After much research I am going manual. Just need to find the correct master and Ill be good to go. Is a 1" bore to much?

Many thanks for your feedback.
Click to expand...

It depends on what you want. Stock power brake master cylinders were 1-1/32", the manual master cylinders were 15/16". The larger bore moves more fluid faster, so you get a higher, harder pedal (which is why they were used with a booster). The smaller bore results in more pedal travel and a higher line pressure, and I find the longer pedal stroke makes it easier to control the brake engagement. A 1" bore would be closer in feel to a 1- 1/32" MC than the 15/16", and personally I like the 15/16". The one I use is sold by Dr.Diff, it's a late model aluminum MC that he sleeves down to 15/16" and modifies for the stock manual push rod.
 
Actually at least the earlier cars used a 1" MC on both manual & disc A-body apps. I used a 1" for mine & it works fine, good feel & stops strong, Wilwood calipers. I'm sure 15/16" would be great as well. I'd be inclined to go with a later aluminum if you don't care about the appearance of the era, the iron original replacements are all Chinese or sketchy rebuilt, I had a heck of a time getting one to work for any period of time & ultimately had to rebuild one myself.
 
I put a 7/8" D MC from a late 90's Breeze/Cirrus w/ ABS (2 ports, dbl-flare), on a 2-4 bolt adapter plate ($30 ebay) for manual brakes in my 64 Valiant. Many others would work. Many here use an 80's Dodge truck alum MC. 15/16" bore would work too, especially for those w/ strong legs.

In some years, the power MC had a smaller bore than the manual MC. Sounds backwards, but not after you consider the lever ratio in the A-body's stand-off brackets.
 
15/16" doesn't require strong legs at all. Now, if you ran a 1-1/32" bore manual set up maybe.
 
BillGrissom said:
I put a 7/8" D MC from a late 90's Breeze/Cirrus w/ ABS (2 ports, dbl-flare), on a 2-4 bolt adapter plate ($30 ebay) for manual brakes in my 64 Valiant. Many others would work. Many here use an 80's Dodge truck alum MC. 15/16" bore would work too, especially for those w/ strong legs.

In some years, the power MC had a smaller bore than the manual MC. Sounds backwards, but not after you consider the lever ratio in the A-body's stand-off brackets.
Click to expand...

Can I use the pushrod out of my dart MC with the late 90's breeze MC? Or do I need to also grab the pushrod from the breeze at the wrecking yard?
 
A 90's Breeze MC doesn't have a pushrod since they mount to a booster. Look for my post on my 64 Valiant w/ manual brakes. The Valiant pushrod fit fine and locked in tight using a new rubber bushing on the tip. The brake pedal wound up in exactly the same place. I did need to super-glue a dust bellows from a Valiant manual MC to the Breeze MC to get that, though anyone creative to come up w/ other approaches.
 
y not go with a hydroboot for power brakes? I put one on my 72 demon and it works great.. it can be a little sensitive but once your used to it its really not that bad
 
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