MBC bleed hole question
Jul 25, 2007, 04:39 PM
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MBC bleed hole question
Since I couldnt find the answer direct answer when I searched, I was wondering when is the bleed hole at what psi level suppose to start hissing when u r doing a boost leak check? Mine started at .5 bar is this normal?
Thanks in advance
Thanks in advance
Aug 27, 2007, 08:44 AM
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Bump to this thread 
I have a Forge MBC, the bleed hole is always open. I've done a boost leak test, the pressure on the system will fall down from 15psi to 0 after 1 min. Is it normal?
Otherwise, the car holds boost to 23psi @ 3500rpm with no problem to 20psi at redline.
I have a Forge MBC, the bleed hole is always open. I've done a boost leak test, the pressure on the system will fall down from 15psi to 0 after 1 min. Is it normal?
Otherwise, the car holds boost to 23psi @ 3500rpm with no problem to 20psi at redline.
Aug 27, 2007, 08:59 AM
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the bleed hole is always open. air is vented out of it when the ball and spring open up. when the ball opens up depends on how stiff the spring is set to, and isn't going to be the same for everyone. because the boost controller is a "restriction", in other words a pressure drop, before the wastegate, when it opens up depends on where you have that "restriction" set to.
the best way to boost leak test it is to take the two vacuum lines on the MBC, and connect them together and take the MBC out of the loop so that it doesn't leak.
the best way to boost leak test it is to take the two vacuum lines on the MBC, and connect them together and take the MBC out of the loop so that it doesn't leak.
Aug 28, 2007, 01:20 PM
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or if you don't want to disconnect your MBC just crank it down 3-4 turns and it should bleed off. You only need to pressurize your system to 15psi (1bar). Just remember how many times your turned the MBC so you can turn it back when your done.
