In EU the engine is 510hp.That Dyno is probably malfunctioning. The graph should show about 429hp, not 443hp. In any case, before starting to question the 505hp of the 2.9L V6 engine derived from the F-154, check the accuracy and maintenance of the Dyno you used. The QVs that we all bought were equipped with 505hp engines. I hope your came with the same engine.