Since you changed the carb, I would look for a vacuum leak around the carb and vacuum hoses. A vacuum gauge can be an awesome troubleshooting tool. if you have less than 18" of vacuum you probably have a leak.
As a baseline you can close then open the idle mixture screws about 1 1/2 turns. This is usually a good starting point. Also as mentioned in the earlier posts, check the timing and firing order.
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