How to max mpg

The best way I know of to improve mileage is to simply drive conservatively. Accelerate gradually because acceleration takes more energy than anything else and use cruise control as much as possible. As far as parts go, the best parts to improve gas mileage are headers, exhaust system, and intakes because these all allow the engine to breathe better. High-powered ignition systems are also good because they burn the fuel more completely, thus allowing the engine to put out the same amount of power with less fuel. The best place to start with an ignition upgrade would be the coil(s), then wires, then plugs. ECU upgrades are also helpful.