I hooked my after market boost gauge to the hose under the sc snout it also runs to my map sensor ...is this where i hook it up to? I teed off the hose but im getting -2 psi. Can i tee off the tree on the top of sc? And i removed the boost bypass so where do i put that little arm that goes into sc? Down touching bottom or in up position?

The boost bypass arm should be all the way down to be closed, you can see that with the SC off.

If It is up then that might be why you dont see any boost?

Okay i just used the search function i got my answers ok so the little arm and hand goes down touching the sc this is the closed position and it should be making boost maybe i have a bad gauge. Its hooked up like all the threads read. Only one difference my fpr is connected to thr tree by brake boost not teed from under snout and map sensor is this ok?

The fuel pressure regulator, the MAP sensor, and your boost gauge should all be hooked up to the vacuum port exiting the lower intake under the supercharger's snout. This is the only vacuum port on the 3800 SC engine that sees both vacuum and boost (unless you have a 96-97 3800 SC engine which also has a 2nd metal vacuum tree on the front of the supercharger - but later superchargers lacked this).

The plastic vacuum tree on the top of the supercharger as well as all vacuum ports on the side of the throttle body see vacuum only. DO NOT connect your MAP sensor or fuel pressure regulator to one of these.

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If you removed the boost bypass solenoid then that could be why you see no boost. If you do not have that small arm bolted in the down position somehow, you just bleed off all of your boost back into the intake

The boost solenoid can be removed from any 3800 SC engine and it will still see boost as long as you don't hook anything up to the bottom port on the boost bypass valve actuator. This port must be left open and not capped off or hooked to anything.

If the boost solenoid is left hooked up to the vacuum lines as it is stock but not wired up to the PCM, then that can prevent boost from building.

Ok so i guess i must connect my fpr to the tee under the snout the po had the fpr connected to thetree ok im going to check my boost . I left the little arm in there but i did cap off the little hole that the evap sent the fumes back in. Also while we are here has anyone installed a cable here to move the arm to make boost or is that just dumb