Popped the head off and it looks a little lean to me. Just curious what the experts thought: Next question is about expansion chambers, I'd like to build one and the more I read about it I think can do it. Played with a couple of programs but I'm wondering if there are any tips and tricks I should know before I get to far? I'm doing some basic figuring but I need to go through my engine with a degree wheel and get some other measurements before I can really do anything... Suggestions on steel and welding processes?