So much for a slipping ring... and now speaking of valve timing, I asked a fella last week how his cam was installed. He didn't know, but wanted to. He was fairly certain it was an old style, single pattern cam. He also did not want to go to extraordinary lengths (like putting a lift gauge on his push rod, or even using a piston stop for that matter); a half-a$$ measuring job would do this time. Sooooo, I told him to remove his valve cover and, on the number one cylinder, rotate the engine until the exhaust valve just started to come back up to close itself. When it did that, lay a flat pencil across the intake valve and the exhaust valve and continue rotating the engine so now the intake valve will begin to go down into the open position. When the pencil is flat, indicating both valves are at the exact same height, read the timing mark on your dampner and that will indicate the advance or retard of the cam installation. For some reason, your post just brought this to mind -- and there just might be somebody out there that would want to check where their cam was after they checked the accuracy of their timing marks. Here's a graph of my cam, as installed, and you can see the "crossover point" is the degree of advance that I have.
