... well I am a father of two boys, have 25 years and a degree in engineering, worked at Jaguar and (quietly now) BMW in Munich, I guess I have a bit of a paternal attitude. Easiest way to improve any engine performance is to allow the engine to breathe properly..or indeed more so. Not only does this mean increasing and smoothing inlet air flow by various means, but also increasing and smoothing the exhaust gas flow. In other words, get as much fuel/air mix in as possible and once it has fired, get it out as quick as possible....Amazing how many so called aftermarket improvements ignore this basic fact...so called performance exhausts being the best con on Earth, as unless your manifold is similarly ported and enlarged, they are never going to do much good.....
Lecture over, now get back to your homework......