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Old 10-07-2018, 08:10 AM   #1
cgster
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Power drum brakes

I had my power drum brake booster replaced about a month ago and really haven't driven it since. Now when I go to drive it I have to stand on brakes to get the truck to stop. If I drive for about 5-10 minutes brakes start working better. Any idea why this would be happening and what I need to do to correct/fix it?
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Old 10-07-2018, 09:09 AM   #2
geezer#99
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Re: Power drum brakes

How much vacuum does your motor produce?
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Old 10-07-2018, 09:23 AM   #3
cgster
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Re: Power drum brakes

I have no idea. It's a 383 stroker engine.
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Old 10-07-2018, 10:32 AM   #4
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Re: Power drum brakes

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Originally Posted by cgster View Post
I have no idea. It's a 383 stroker engine.
You’ll need to beg, borrow or steal a vacuum gauge and hook it up to a manifold vacuum source and find out.
Your booster needs likely a minimum of 12 to 14 hg of vacuum to operate. If your motor doesn’t produce enough vacuum you’ll need to increase the vacuum by fine tuning your motor to get the vacuum higher. Or you might need a vacuum pump to increase the vacuum to the booster.

What are the specs on your motor?
What cam?
What carb and intake?
What’s your timing curve like?

Where in Texas do you live?
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Old 10-07-2018, 11:00 AM   #5
toolboxchev
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Re: Power drum brakes

Geezer is spot on. Most guys opt for the Hydra-Boost unit from later model GM vehicles to make it a gripper.
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Old 10-07-2018, 11:15 AM   #6
cgster
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Re: Power drum brakes

Just looked at it again and found the brake booster fitting was cracked. I'll replace it later today when I make it to the parts store. Hoping that will be the fix.
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Old 10-07-2018, 06:42 PM   #7
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Re: Power drum brakes

Yeah, not much vacuum assist from that bad boy.
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Old 10-07-2018, 11:22 PM   #8
Zone47
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Re: Power drum brakes

Since we're on this topic, will a booster from say... a 69 Camaro work? I have Factory item usually seen in Chevelles and Camaros... one that is tilted back on the bracket a bit but the rod looks like it will hook up properly. I might have to fab something different for two bolts of the bracket.

Any chance of using that?
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Old 10-08-2018, 01:09 PM   #9
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Re: Power drum brakes

Quote:
Originally Posted by Zone47 View Post
Since we're on this topic, will a booster from say... a 69 Camaro work? I have Factory item usually seen in Chevelles and Camaros... one that is tilted back on the bracket a bit but the rod looks like it will hook up properly. I might have to fab something different for two bolts of the bracket.

Any chance of using that?
No
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