Double check my engine builder please 340 stroke

3) Builder recommended 750cfm carb. I like Edelbrock’s AVS carb...is he 650cfm too small or 800cfm to large for a street driver?

I can't help with cam and compression, but there seems to plenty of help for that. I can tell you that I run an 800 cfm Edelbrock on my 408 street driven with no problems. We ran it on a chasis dyno and the A/F ratio was great straight out of the box. Sent the jet kit back to Summit unopened. I think there's one for sale here on FABO right now.