I'm going from the crappy metering plate 600, to the 670 Street Avenger. Can anyone tell me if there is going to be a real big difference? Prob not, but it'll be much better as far as tuning goes. If it wasnt for the crap weather, I'd be cruising the thing around already.

 

Steal the secondary metering plate (#21) from a "crappy" 3310 750cfm vs. holley.
While you're at it get the larger throttle plate assembly too from a 750 carb. Instant 650cfm carb.
Buy a quick change vacuum housing top and secondary spring kit and some accelerator pump cams and shooters.
Use #64 to 68 primary jets.
cut off the choke housing and contour the top of the carb
with a dremel and stones like a HP series carb, to improve airflow.

More difference here than buying a new 670carb.
Less $$$ too.

This will get you at least 700cfm and more power while retaining the street flexability of a small venturi 600cfm based carb.

 

Yeah I knew I should have posted here first, but theres no use in crying over spilt milk. Fact is, the 600 was doing fine for the first couple of years, just recently started fouling up on me, so I just went ahead and bought this 670. I've never been inside a carb(other than taking the front and rear bowls off), now I have the 600 I can fool around with and still have the 670 on the car. I'll go ahead and do the things you mentioned to the 600, then that will maybe teach me some things. Thanks for the info F-Bird'88.

 

is there any drawback to removing the choke on a carb like a 3310....750 cfm VS. assuming that i only drive this in weather above 50 degrees and it's only a friday night cruiser/strip car. Also, do you have a pic to show me how to contour this choke out?