[Rick Norwood]

O.K. here is my two cents worth. I saw that the Distributor was replaced, but with what?
An AC-Delco or an Aftermarket Distributor?

If you take the Distributor cap off can you see or feel any play in the shaft when pushing on it with hand pressure (will it wiggle)? You should not have more than a few thousandths movement.

Do you have an AC-Delco Cap and Rotor?

Have you checked your Timing Chain for slop? Excessive timing chain slop will cause your distributor to jump all over the map. It is very easy to check. Here's how:

1. Remove the Distributor Cap.

2. Rotate the Crank Shaft Pulley with a socket wrench in the same direction as it runs normally and watch the needle on the Distibutor Rotor move. I like to line up the rotor with a mark or something.

3. Then, click the Socket wrench the other way and rotate the engine in the opposite direction. Mark the crank shaft pulley before you start and see how much movement there is on the pulley before the Distributor Rotor starts to move.

4. I can't say how much is too much or about right, but if the pulley is moving more than 3/4 to 1 inch or more before the rotor moves, you probably have a sloppy Timing Chain.