couldn't you in theory have a registered importer do it because Motorex crash-tested them and the document describing the changes necessary is available for public viewing, granted it doesn't say what is needed for to change the engine to make it EPA legal, but couldn't that be recertified fairly easily or at least less expensively than the crash testing
R34 for your time
P.S. This guy (second answer down) has absolutely no idea what he is talking about, and 107 people agree with him!!
the US police force cars can't keep up with it? quite a load of bull, Crown Vics can't keep up with aventador, a gallardo, or a veyron, and they are all road legal.