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Cman60 · 05-24-2017, 12:16 PM

Are you sure the ping is a ping? Sounds like you might have a broken valve spring. Good idle, but when RPM increases the valve is slow to close. I would pull the valve covers and see what you see. I would also pull the spark plugs and see what's going on there, e.g. color, and any damage to electrodes.

BUT before I did any of that, I would check total timing/advance curve. You only checked static timing at idle. Find the timing chart for your engine and compare the spec with what yours is doing at various RPM. This will reveal any problems with fly weight springs in the distributor.

05-24-2017, 12:16 PM	#14
Cman60 Registered User Join Date: Feb 2017 Location: New York, Hawaii & elsewhere Posts: 19	Re: 1972 Cheyenne 350 Engine problem Are you sure the ping is a ping? Sounds like you might have a broken valve spring. Good idle, but when RPM increases the valve is slow to close. I would pull the valve covers and see what you see. I would also pull the spark plugs and see what's going on there, e.g. color, and any damage to electrodes. BUT before I did any of that, I would check total timing/advance curve. You only checked static timing at idle. Find the timing chart for your engine and compare the spec with what yours is doing at various RPM. This will reveal any problems with fly weight springs in the distributor.