Why change headgasket is it overheating or mixing fluids ? and no your ecu tells the car how much fuel to spray no more/no less its not about adding more fuel making power is in how much timing the engine can advance before detonating (doesnt mean blowing up) , literally not a single intake tube/filter will make anymore power than the stock airbox esp with a k&n drop in filter, aluminum intake and cone filter sounds nice but raises intake charge temps ='s easier detonation , aftermarket intake manifold with corresponding bolt ons will make more power but like I said if you want to make power a swap is the key, and your post/comments show your knowledge ... its not even about timing a mini me... lol and also you time a mini me by using all the stock pulleys cam/crank for timing belt/water pump must match and uses oem timing marks, vtec headgasket/head bolts