The Stovebolt Site Forums The Shop Area Engine Shop timing a 41 gmc 228 engine

I am trying again. Do you time a GMC or any chevy of 1941 era with the vacuum advance connect or disconnected to the distributor ? The engine is timed fairly well but when you hit the throttle it advances very quickly and will back off, when you release, but not totally. There is nothing wrong with throttle setup on the Zenith. Suggestions please or comments. Thanks Doug P.S. I timed it without the vacuum connected.

Hy doug one, although it is never actually spelled out in any instruction I've read, I believe the intent was to set the timing without any vacuum or centrifugal advance. The instruction for static timing (not running) the engine says to make sure the vacuum advance is in its full retard position. The instruction for for timing a running engine with a timing light says to keep the engine at idling speed so that the centrifugal advance does not come into play. So I would say that disconnecting and plugging the vacuum advance while timing the engine with a timing light would not cause any problems. I hope that helps.

Thanks, appreciate it, Doug