40hp is a joke on a small electrically driven turbine like that; sounds like false-advertising at the cost of time and money. If anything, I would think you'd lose power by having that piece of junk in between you and your intake.
But if you have an hour and 60 dollars to waste, buy it and try it out.. maybe it has a voodoo aspiration spell cast upon it (would certainly make us all look like jerks). If it even generates half the power that it's claiming, I'll swallow my vomit and buy one.
And, aye, the Mass Airflow Sensor is what the computer uses to determine the correct air/fuel mixture. A popular and relatively inexpensive mod, aside from swaping your chip, is to replace the MAF with one designed to give slightly modified readings (good luck passing emissions inspection on that one).
I would be more concerned, however, with mounting that turbine. The author's recommendations also seem somewhat interesting. He recommends using a cold-air setup and having an increased exhaust (it's no good when your engine can't let out the increased air it's taking in). These mods alone might yield half the power he's talking about (in the 20hp range, depending on other mods).
But I don't know.. I'm the furthest thing there is from being car-savvy. If you've got 60 bucks to lose, tell us how it works out.
'01 GTP: 3.3" pulley, Headers, 3" Exhaust, Straight Pipe, Intense Air to Water Intercooler.
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Old Ride: 95 Mystique LS V6 ATX:
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