Where did you see up to 600hp?I don't think any American company has one yet. Gale Banks is working on one, I believe. There are European tuners for the motor, but I'd stay away, until an American company like Banks, Bully Dog, Edge, Diablo have one. One thing for sure, it's a very stout designed motor. Banks is talking about 600 hp!! When that happens, I'll be selling my hemi. BTW xtremediesel.com has exhausts and cold air intakes for the Ecodiesel.