If a stock L24 is rated at 151hp gross, and an L28(75-78) is rated as 170hp gross, then why does the Chilton repair guide rate the L28(79-83) n/a as 132-145hp gross? Why then would anyone want the F54 block over an N42 in stock form? I've seen the info on other internet pages state the F54 stronger than the N42 (for turbo reasons) and extra water jackets and compression heads but why bother unless for all out crazy power? Who should we trust, other internet guys or manuals (said with all do respects). Thanks for any input.