After re-reading this thread, I'm wanting to say check for leading spark. Also double-check to make sure you didn't get the primary and secondary main fuel jets backwards. That could cause problems like you are having. Check compression as well, to make sure you don't have any blown seals. That idle screw shouldn't have much effect once you start opening the throttles. Try that and let us know ...

 

Don't sell the car. If you are reaching the limits of your patience with your carb, then pick up a used one on the forum for 50 bucks. Or, find a friend with a working carb and swap it on for troubleshooting (verifying that your issue really is the carb).

Used carbs are cheap, and you can often find one that just came off a good running car.

Hang in there.


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