We are offering a header for the 4 stroke motor. Header is a bolt on piece. Header is ceramic coated, and weight with coating is 5 1/2 lbs. Stainless Steel header weight is 6 1/2 lbs. Recent dyno testing shows a 7 - 8 hp gain at 8200 RPMs. The header does not require a fuel box. The Gen 3 controller box is available in 3 different levels. The Gen 3 controller adds fuel by offsetting the pulse width a given fixed value. The Gen 3.2 controller box can add fuel by offsetting the pulse width or by adding fuel by calculating a percentage of the stock injector pulse width. The Gen 3.5 controller box can add or subtract fuel by calculating a percentage of the stock injector pulse width. When ordering header please specify if using an air/fuel ratio gauge. The Power Commander V fuel injection module has arrived. The muffler is now available ceramic coated with a weight of 6 1/2 lbs.