Where can boost go besides through the engine and out the exhaust? Can it escape out anywhere like the opti fresh air hose? I assume it has a check valve and will close when it hits boost. Does the manifold rear and front leak i see so much have anything to do with the air flow? I know of the obivious place like the tubing going to the throttle body so where else can it go? I have wondered about a leak or something so i can get more performance.

 

Check all your clamps and hoses from the blower to the TB. Its very possible to bleed off boost if somethings not tight. Take your time looking, as even a small gap say in your IAT sensor plug could leak under boost conditions.

 

Regarding the opti vent line, that line should be on the suction side of the blower not the boost side.

You can also lose boost through belt slip, collapsing intake tube, or through an intercooler leak. Should pressure test your intercooler if you're running one.

 

Joe has a good point. Also be sure to check all the points on the intake like the vacuum lines, the egr block off plates if you are running them ect. Theres more than a few of them and its possible to have a leak there as well. More than likely it is a leak somewhere between the blower and the TB though, and like joe said, the intercooler is a big part of that if you have one.