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??

 

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.

 

Cam's not "big", but the 107 LSA increases overlap and reduces engine vacuum at low RPM.

 

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.

 

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?

 

It's the divorce that really hurts

 

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?