1978 Chevy Malibu bad brakes

1978 CHEVROLET MALIBU
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PSI3000
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Brakes problem
1978 Chevy Malibu V8 Two Wheel Drive Automatic

This is a drag car. I recently rebuilt the engine with a Trick Flow 400 HP+ top end kit. Now, the power brakes don't work very well. They were fine before. Master cylinder is about a year old. No fluid or vacumn leaks. Breaks have been bled (a few times). Makes it tough to get a good launch because the cars starts to creep forward before I can get the RPM up. Iv'e been told that the bigger cam cannot produce enough compression fro the brakes. What do I need to do?
Sep 21, 2009 at 5:58 PM
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JACOBANDNICKOLAS
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I'm confused. Actually, the compression has nothing to do with the brakes. However, vacuum does and it sounds like what you have done will produce more. Is the brake pedal dropping too low to the floor? Have you lost power assist?
Sep 21, 2009 at 10:03 PM
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PSI3000
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Maybe i should have said vacumn instead of compression. When the engine is running and I push and pump on the brake peddle, I get almost nothing. It doesn't get stiff or tight like it should and goes all the way down. I have to really stand on it to get good braking. Don't think I know what you mean about power assist.
Had another guy tell me to go to a manual brake (not power) master cylinder. I've searched the internet and can't find anything called a manual brake master cylinder.
Sep 21, 2009 at 10:46 PM
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JACOBANDNICKOLAS
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Have you replaced the master cylender? Checked calipers, wheel cylenders, lines for leaks? I don't recommend the manual brakes for this car. Especially if it is as fast as I believe it would be.
Sep 22, 2009 at 6:44 AM
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PSI3000
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I think I have it figured out. I talked to a few racing guy's. An engine with a big cam will never produce the required vacumn to support power brakes. I have to change to manual brakes or install an electric vacumn pump.
Sep 22, 2009 at 9:15 PM
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JACOBANDNICKOLAS
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That is interesing. I would have thought the opposite. Let me know what you decide, a vacuum pump or manual and how well it works for you.
Sep 22, 2009 at 9:20 PM