I gotta agree with Nairb.
With all the mag making hype about power production and how affordable it is this aggressive marketing stratagy has led people to beleive that 500hp is an easy mark to make. But if these people who claim it take it to a unbiased dyno operator, it's easy to see it ain't as easy as 1, 2, 3, but still possible. Most can't do it with strictly bolt on part's. Or make it without huge rpm and reducing reliablity.