What's a good checkvalve...
A check valve that blocks vacuum, will also hold pressure in the reference line. This will cause problems.
If you only want boost & no vacuum, run the reference line to the pressure tubing in front of the throttle body. This way it will see only boost.
FYI vacuum will not effect the fuel flow at idle that much (5-8% depending on manifold vacuum) so you may want to try it connected to the manifold first.
Call me if you need additional assistance.


