Note: This thread was lost in the Great MA Bit Bucket Debacle of 2010. We had some very good discussion and education going on headwork. I managed to reconstitute a few posts from the Google cache - but not all pages were there. I appreciate your efforts to restore some of the content you had provided previously! **** Since heads have become an off-topic topic of a number of threads, I thought it would be fun to have a thread dedicated to headwork discussion so we can then turn it into a thread about cams or suspension or something like that. Ground rules: this isn't a thread for pitching whatever head you're selling. But it IS a thread for discussing pros and cons of different approaches to headwork, trade-offs of various types of head improvements, and general education of the unwashed masses on how and why headwork works. To kick it off, I found this very good article this morning. Required reading for anyone who wants to participate in the discussion. Otherwise I'll call you out and say bad things about your momma. Secrets of the Cylinder Head - Tech - Sport Compact Car Magazine I thought this did a particularly good job of describing the art and science of valve jobs, of which I previously had a poor understanding. But it also covers porting in general, and flow vs. velocity considerations.