You guys have explained to me about ivc, also on how to figure it out. If I'm understanding things correctly the stock 318 cam has 55* ivc and the 340 cam has 69* ivc, wouldn't closing the intake valve later lower the stock compression more? I don't mean to be a pain but how can the 340 cam wake up the 318 if it does lower the cr? I enjoy learning what I can. Wanting to build a engine going by pure stock rules but having a little work done to the cylinder heads.