I'm interested in building a modified clone, to race in the outlaw division at my local track. I'm new to engine building, and don't want to spend a large sum of money, so I'm trying to keep this simple and basic. Billet flywheel and rod, flat top piston, gx390 carb, oversized valves, and a dyno 308 cam are what I'm planning on using. My question is....should I have the cylinder bored .030 over? How many more cc's would this add? Would it add much power? and would it lower my compression? Also....with the 308 cam, how much will I be able to have my head milled, without the piston hitting the valves? Thanks so much for any and all answers. Like I said, I'm new to this and would like to learn as much as possible, and there is no better place to learn, than from the experts here at Bob's. Hope everyone has a great Thanksgiving!