Severe bogging, surging under load...

[effinrich]

This is my first time posting, so I'll try to do this right.

I recently replaced the mag. pickup coil in the dizzy. I was sloppy about the dizzy reinstall and knocked the timing way off. Over the next few weeks, after getting a timing light and researching, I was able to get the timing straight. The fuel pump was bad, so I switched that out at the same time.

Upon driving the first time after all of the work, the truck started out pretty good. After driving it for roughly twenty minutes it started boggin down, surging, and lunging on even the slightest incline. The gas pedal looses pressure, the RPM's jump back and forth from 3000 to 3500 just to get it up to 40 mph. There's also a steady clicking or tapping noise coming from the engine during all of this. Sounds like a card in bicycle spokes.

I thought the timing was still off, so I set it again and again with the same bad results.

I've adjusted the carburetor which seems to effect it to some degree, but nothing dramatic enough to make it drive well.

Thought is may be the ignition control module, so I changed that out, as well as got new plugs and wires.

I'm going nuts trying to figure this out. Any thoughts would be extremely appreciated.

The truck: 1965 GMC 1000, HEI dizzy, 350 crate, Edelbrock 1406 carb, 63 amp internally regulated alternator.

Recent work: New alternator a cpl months ago, replaced the dizzy pickup coil as the magnet on the original cracked, new ignition control module, new plugs, new plug wires, new fuel pump, new sending unit.

thanks!