That is extremely odd.

By unrestricting the intake..you should be seeing higher boost as you've thought. Why this intake and no intake would lower your boost is...really wierd.

I am thinking about why you would get more boost with the stock intake...it doesn't make sense though. Do you have the screen in the throttle body..right at the entrance to it.?

Yes there'* a screen

I don't know if mine is having a similar problem or if it is a gauge problem; my 94 SSEi (stock airbox) reads at the far left side of the boost gauge (the negative side).
It only gets up to the "0" mark or into positive territory if I'm accelerating hard. Has anyone else seen this sort of thing?
Thanks.

Quite an old topic, may not be related. Please start a new topic in this section for your problem.