Has anyone had their DC header dynoed before? either the 421 or the 4-1?
I'm thinking of getting the 4-1 for my GS but then I've read lots of different reviews on them.
I know 4-1 is directing the power to high end and 4-2-1 is mid range. But i've read that it is better to go with 4-2-1 for LS motors cuz we dont have much of high end anyways.

does anyone have dynoed their header to see any actual gains on both of the headers?

Tommy