alternator w/vacuum pump
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Joined: May 2014
Posts: 81
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From: Washington nj
alternator w/vacuum pump
Hello all.
Wondering if anyone has ever used one of these or have any info on them? I'm only getting about 8Hg of vacuum from my engine , and need to increase vacuum for the power brake booster. Was trying to keep costs down and looking at 12v vac pumps and came across these.
Thanks Brent
Wondering if anyone has ever used one of these or have any info on them? I'm only getting about 8Hg of vacuum from my engine , and need to increase vacuum for the power brake booster. Was trying to keep costs down and looking at 12v vac pumps and came across these.
Thanks Brent
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,116
From: Crossville TN
You should first verify that your engine CANNOT provide an adequate vacuum level. Nearly all Chevy V8 engines will make 10" Hg or higher. Stock engines make around 17-20" Hg at idle.
Remove/block off ALL connected vacuum lines to the carb and intake manifold...except for the distributor vacuum advance can. Start warmed up engine and measure vacuum at a 'manifold' vacuum port (intake or carb).
If you still have 8" Hg or less, buy the alternator/vacuum pump. If you find that you are getting over 10" Hg, do some diagnostics to find the source of your vacuum leaks, fix them, and let your engine provide the vacuum. With 10-13" Hg, you will definitely need a good check valve and vacuum reservoir tank included with your vacuum system.
P.S. Make sure that alt/pump item has a "vacuum" pump on it...not an "air" pump. {Or, if it's an air pump, plumb it backwards.
}
Remove/block off ALL connected vacuum lines to the carb and intake manifold...except for the distributor vacuum advance can. Start warmed up engine and measure vacuum at a 'manifold' vacuum port (intake or carb).
If you still have 8" Hg or less, buy the alternator/vacuum pump. If you find that you are getting over 10" Hg, do some diagnostics to find the source of your vacuum leaks, fix them, and let your engine provide the vacuum. With 10-13" Hg, you will definitely need a good check valve and vacuum reservoir tank included with your vacuum system.
P.S. Make sure that alt/pump item has a "vacuum" pump on it...not an "air" pump. {Or, if it's an air pump, plumb it backwards.
}
Last edited by 7T1vette; Jul 24, 2014 at 12:22 AM.
Race Director
Joined: May 2003
Posts: 10,956
Likes: 409
From: California
I have been looking into the vacuum pumps as well..... Cadillac uses a electric one and I have been reading some have gotten over a 25hp boost at the Dino using them... They help relieve back pressure on the pistons, and help with ring seal..... At least that is what I have read... But I want to use one for my PCV system with a catch can.
I went hydro boost with the brakes...... One of the 5 top best mods for the C3 IMHO
I went hydro boost with the brakes...... One of the 5 top best mods for the C3 IMHO
