Carb CFM help

The 360 in my Cuda is very similar to yours and I have had 600, 670, 725 and 750 carbs on it. The 600 and 670 have great low mid rpm throttle reponse. By the But dyno there is no difference between the 670, 725 and 750 carbs. The 725 and 750 don't have anywhere near the throttle reponse in the low mid range and get about 5 mpg less than the 600 or 670. If you are following along the 670 is the best all around carb.

The 670 is a Holley Street Avenger. My second choice would be the 600 (a generic Holley vacuum secondary carb) becasue of the great throttle response and it doesn't really give up much on the top end to the bigger carbs but it is noticeable to the butt dyno. My third choice would be the model 3310 Holley 750 and the 725 Demon is last.

For a daily driven street car I wouldn't but a double pumper anything on it. Unless you are a very talented carb tuner you will give up to much low mid range driveability and gas mileage for little or no improvement in the top end.

FWIW, my car has run a best of 13.7 seconds at 102 mph in the 1/4 mile with the 600 cfm carb so the small carb is not really holding it back much. That is with a very traction limited 60' time of 2.2 seconds and an A833OD tranny.