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**jocko** · 06-16-2013, 01:11 PM

what musicman said - 18 is about what you want to have, minimum. I've known folks to say 16 was enough, but that is the very lower end. If you have a lopey cam, expect to be on the borderline of having sufficient vac to operate the booster. It is possible to add a vacuum accumulator that will help power the booster in addition to the minimal engine vac, but I never really wanted to hang one of these things in my engine compartment.

I've never seen or heard of a booster that requires less vacuum than another one. I suppose there could be minor variations based on design (dual vs single diaphragm, etc) - but nothing is manufactured/advertised as being able to operate with less vacuum that I'm aware of. That is why the vac accumulators are made.

How much vacuum do you pull with your lunati cam on the bb?

06-16-2013, 01:11 PM	#9
jocko Senior Member Join Date: Oct 2009 Location: Godley, TX Posts: 17,995	Re: Power Brakes/Vacuum???? what musicman said - 18 is about what you want to have, minimum. I've known folks to say 16 was enough, but that is the very lower end. If you have a lopey cam, expect to be on the borderline of having sufficient vac to operate the booster. It is possible to add a vacuum accumulator that will help power the booster in addition to the minimal engine vac, but I never really wanted to hang one of these things in my engine compartment. I've never seen or heard of a booster that requires less vacuum than another one. I suppose there could be minor variations based on design (dual vs single diaphragm, etc) - but nothing is manufactured/advertised as being able to operate with less vacuum that I'm aware of. That is why the vac accumulators are made. How much vacuum do you pull with your lunati cam on the bb?