Due to the fact that I had been experiencing overheating issues with my 454 powered 67 Chevelle I had done some researching on the “Interweb” and found some interesting articles about vacuum advance. Initially when I put my engine together I found an article that stated “High performance engines do not require vacuum advance”. I read it and it made sense to me so I did not hook up the vacuum advance. I had overheating issues and the engine ran hot even cruising down the road. At a later date I came across a different article that said all street driven cars need to be running vacuum advance. Last summer on one very hot day some friends and I were going on a drive for a couple hours and I thought it would be a good time to test out what was said in the second article. The engine ran cooler and after heating up in traffic it would cool down once we got going down the road again. Following is a link to some info pertaining to vacuum advance.