i had always heard that with a turbo or super charged motor that polishing the intake would not be a big H.P. gain. the turbo forces the air through the intake super fast anyway.
just my 0.2 cents
P.S. b stokum does this kind of thing for the na pt cruiser's . they are modifing the gt cruiser intake's to fit on the na cruiser.
here is his site
http://www.bstockum.com
thanks tommy