Jason,
The correct cam/valve timing can be verified by just removing the valve cover and spark plugs (for easy rotation) and observing that overlap position for 1 or 6 occurs when the TDC marker shows TDC.
Overlap is the position on top center end of exhaust stroke where the inlet is just opening and exhaust is just closing.If perfect both will be off the seat equal amounts at TDC.
Moving the crank BACK and FORTH from about 5 degrees BTC to 5 degrees ATC should show the valves equally open.
The results will vary a little if the valve adjustment is much too loose.
One tooth off will make a difference that is easily discerned.
And yes if it is a tooth off the vacuum will be low and performance affected but it will run pretty good--at some speeds and loads--if the spark timing has been optimized.
I think you are looking at your next best test in anylizing your problem.
Last edited by enginenut; 12/28/2011 7:02 PM. Reason: mistake
