Can't find it with google search.a tv show debunked this myth recently. they smashed the hell out of headers and the engine made more HP at one point but over all lost almost nothing. dyno's don't lie. micron used to have a set of headers that also proved this theory as a myth. just google micron serpent headers and you will see what I'm talking about.
Thanks for the video, some great empirical evidence there.youtube
Is this what you guys are talking about?Can't find it with google search.
Do you have a link?