A 44 HP gain by going to headers from stock HP manifolds? That is a LOT!

BUT, I will say this - I don't think Nick would doctor this & pull some funny stuff behind the scenes. If he's just swapping from the stock, to the Max Wedge, to headers, & doing dyno pulls, then I think we are seeing actual true results. I'm just really surprised there is that much of a difference. In this test, the stock HP manifolds are the baseline so he's doing the comparison right.

Did any of you watch the denting-the-headers test that Freiburger did on Engine Masters? They almost CLOSED several of the primaries before they started registering any HP losses on the dyno. That was quite an eye opener. Toward the end, I can guarantee you by the time they were 3/4 of the way through the experiment, those headers were not flowing well.