Thread: I really am idling with 40 degrees advance

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Believe me, your engine is NOT idling with 40 degrees advance. You are timing it on the wrong cylinder, or something. It would kick back and blow the starter off before it ran like that.

IF you have your idle RPM set above 800 and you are running FULL manifold vacuum to the vacuum advance , then you may be running 40 degrees advance at that idle. This would depend on how much mechanical advance and vacuum advance is being added to the initial at your idle RPM.

The correct method to check/set the timing is to disconnect and plug the vacuum advance hose from the vacuum advance cannister. You should also have the trans (if automatic) in drive (be sure to set the emergency brake and block the wheels and do NOT rev the engine up when checking this way. Also would be a good idea to have someone with their foot applying the brakes.) and the idle should be in the 650-750 RPM range.

Checking at a higher RPM will cause an incorrect reading as the centrifugal advance weights will have begun to open and will cause some additional timing.

Checking with the vacuum advance hooked up will also cause an increase in the timing since their is no load on the engine the vacuum advance unit will also increase the timing.

You are checking the timing incorrectly.