Actually it wouldnt be 336, because 20% of 336 is 67.2, and 336-67.2 is 268.8 hp, and not 280.....it should be 350hp b/c 20% loss is 70hp which is 280 whp. If they say its 320 at the crank and 280 at the wheel that is a 14.28% drivetrain loss and not 20%, 20% would have been 64 hp loss. :nice...