Does denting your headers cause a loss of power?

That's awesome! Makes me feel a lot better about my old fender well headers!! Anybody want to buy a "modified" set of hooker super comps for a big block a body?!

No thanks... when I built my first big-block A-body around '83, those Hookers were about the only option! Don't know if the Hedman B-body units existed then (but nobody knew about them, and no Internet to spread information).
Anyway the Hooker fenderwells were a real hit: They hit the tires. They hit the ground. They hit the body... and that was with a 383. I swapped to a 440 later and the fit was even worse.