It's hard, got to take a lot with a grain of salt, even the experts don't always agree so it hard for the little guy. If I was you I'd get David Vizard's "how to build horsepower" and "performance with economy" get those two books go over and over them till it sinks in and that will give you a basic foundation to build on. I'm not saying David Vizard is the final word or even the best, but you could do a lot worse and he gives a very complete understanding of the entire drivetrain, plus I'd watch all of Richard Holdeners videos a bunch of times no other place your gonna get a bunch of dyno information. That should give you a decent understanding to work from.
