I have a Single inlet dual out super 44 muffler and wanted to know if anyone out their was running headers and if they really helped add much horsepower or what. If not whats the next thing to add to gain some ponies or gain MPG's? I have an exhaust, a intake and getting a tuner for christmas

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2002 Wedgwood Blue 4x4 |CAI, Dual Gibson Exhaust, Re-tuned | Exterior/Interior LED
Painted Interior | Painted exterior trim and black chrome
Black Leather Racing Seats | Black Carpet
Dual Headunit | Pioneer Speakers 180 W ea.
ATX 16x8 wheels on 30" BFG | 5% rear tint 20% front | Headlight Mod | 8K HIDS