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68gmsee · 07-03-2009, 12:52 PM

Assuming it's running rough because of ignition, I'd play with the timing to find the best setting. With the hose to the vacuum advance plugged, I set mine at 8 degrees on my 250. You can start at that and go higher to see what your truck likes.

I've got the plugs at .040 but some guys here prefer .045 -again, whatever makes it run better.

However, after saying all that, you may want to check to make sure your distributor rotor, cap, internal ground wire and all parts are good. Don't forget the plug wires.

There are other things that can make for a rough idling engine including valves and cam, but I guess you have eliminate them one at a time.

Good luck...

07-03-2009, 12:52 PM	#2
68gmsee Active Member Join Date: Jul 2007 Location: Centrally located between Houston, Austin and Waco. BCS area. Posts: 7,947	Re: 292 tune up question Assuming it's running rough because of ignition, I'd play with the timing to find the best setting. With the hose to the vacuum advance plugged, I set mine at 8 degrees on my 250. You can start at that and go higher to see what your truck likes. I've got the plugs at .040 but some guys here prefer .045 -again, whatever makes it run better. However, after saying all that, you may want to check to make sure your distributor rotor, cap, internal ground wire and all parts are good. Don't forget the plug wires. There are other things that can make for a rough idling engine including valves and cam, but I guess you have eliminate them one at a time. Good luck...