340 w/ edelbrock 750 need to know what jets to put in the carb.
OOTB jetting should ba a tad rich, but not to bad. What you'll really need to do is look at the plugs and determin which way to go. I'll bet you'll step down 2 jet sizes, but wait until you read the plugs.
Other factors that would effect the jetting is the weather and other engine parts changed out like headers, ignition, air cleaner etc.....