LT1 Based Engine Tech 1993-1997 LT1/LT4 Engine Related

Brakes suck. The camshaft is robbing my vacuum.

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Old 08-09-2010, 04:52 PM
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Brakes suck. The camshaft is robbing my vacuum.

Been chasing a hard braking condition under panic stop conditions. All braking components have been determined to be good including the master and booster. I have to stand on it to make the ABS kick in under panic stop. FTR I have 12" LS1 brakes too.

For giggles I put a vacuum guage on the intake and I have:
12" at idle with AC off
10" at idle with AC on

Stock cam made 20"-22" IIRC.

I am confident I dont have any vaccum leaks. Motor runs well and BLMs are near perfect. So its the cam robbing my vaccum that is affecting my braking. I have a 224/230 which aint that big. But its on a 107 LSA with lots of overlap and according to folks who are smarter than I am, thats what is doing it.

What are my options here other than replace the cam with a tamer LSA??
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Old 08-09-2010, 07:20 PM
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Just fixed my friends brakes with low vacuum by putting in a vacuum cannister between the booster and vacuum supply line. Much better than it was before.
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Old 08-09-2010, 10:45 PM
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Cam's not "big", but the 107 LSA increases overlap and reduces engine vacuum at low RPM.
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Old 08-09-2010, 10:48 PM
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Try a vacuum canister. I have to run one on my car to get any kind of power brakes.
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Old 08-10-2010, 10:41 AM
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Originally Posted by camarobird92
Try a vacuum canister. I have to run one on my car to get any kind of power brakes.
I did and I saw little to no improvement so I pulled it and sold it.
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Old 08-10-2010, 11:46 AM
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Here is my fix for crappy vacuum/brakes.

http://www.cvrproducts.com/vacuum_pump.html

Give a pep talk to your wallet it's gonna sting.
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Old 08-10-2010, 11:53 AM
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Originally Posted by WS6T3RROR
Here is my fix for crappy vacuum/brakes.

http://www.cvrproducts.com/vacuum_pump.html

Give a pep talk to your wallet it's gonna sting.
$400.00 for something that sucks should be against the law .

What is your vaccum without the pump?
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Old 08-10-2010, 11:26 PM
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Originally Posted by wrd1972
$400.00 for something that sucks should be against the law .
It's the divorce that really hurts
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Old 08-11-2010, 01:17 AM
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Just go to the yunkyard and get a brake booster vac pump from a '04 silverado for $30.
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Old 08-11-2010, 06:22 AM
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Originally Posted by MikeGyver
Just go to the yunkyard and get a brake booster vac pump from a '04 silverado for $30.
Is this what you are referring to?
http://cgi.ebay.com/ebaymotors/03-04...Q5fAccessories

Is that a pump coupled to a resovoir?
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