[Jerry Cowing]

Mike,

Sorry about all your problems, it can really be frustrating running down electrical problems. Those invisible electrons make it hard to see if something is broken. :-) It's much easier to find a leaky radiator hose.

When I start having problems like this, I like to step back and start with the basics again rather than keep changing things.

You stated the car was worked on and then was backfiring through the carb, etc. That tells me that the timing is off. What could cause this? One is the electronic ignition which is what you seem to be concentrating on. The other is that the distributor could have been installed wrong. It could be one gear or more off. Your electronic ignition can compensate for a misaligned distributor a little, but not at all RPMs.

After you pull the distributor and make sure it is aligned correctly, then disconnect all your electronic ignition wires and one by one make sure they are connected per the ignition instructions.

A third timing problem could be the cam was indexed wrong when they re-built your engine. There might be a way to check your cam index without pulling the cam cover, but I don't know that procedure.

Finally, it could be your valves are adjusted too tight and that's why it's backfiring through your carb. If you have hydraulic lifters, this is probably not the problem, but if you have solid lifters ...

I'd definitely go back to these basics and check your valve adjustments, distributor, etc. before you redesign your electronic ignition system and burn something up.

Good Luck,