Not speaking for Eric, however, the horsepower statements are not derivative of intake temperature drop, but rather from the increased flow rate of the plastic manifold over the aluminum 3.2 intake. As well, the comments of "fastest porsches on the planet" most likely stem from Billet Designs build ups of drag porsches running the quarter mile in the 8 second range.
I don't have a dog in this fight, so be gentle...
JP