Has anyone ever done any real back to back tests between the FMF Power Bomb header and the FMF Hi-Flow header? If so what were the results? Where in the rpm range were the changes. Does any one know what are the differances between the two other than the power bombs chamber?(bigger tube diameter?) Ive got an xr with the stage two Hot Cams, opened air box, uni, JE 11.1 piston, FMF Ti4 muffler , mid pipe and Im up in the air on the head pipe. Street only and at 5200 ft. thanks..