I didn't remove the rocker arms, I just depressed the spring and rotated them to the side, worked like a charm, then I didn't have to adjust the valve spaces.
Not always and it depends on what performance mods. The way to do it is to have a plan that includes how much RPM you intend to run. A solid understanding of gearing is an important part of the plan. A good reference to start with is 4500-5K RPM. If you know for sure that you will not run faster than that you could risk running without a billet flywheel. More RPM than that you should use a billet rod and flywheel. Let's say you don't care to learn about RPM and gearing. That's when you start with a billet rod and flywheel to be safe. With a billet rod and flywheel it's a better engine than stock no matter what RPM you run.
