Time for a New carb

Just put a 670 Holley Street Avenger on my 360 to replace the 600 Holley i had been using. It was truely a drop it on and go exercise. My gas mileage jumped from 15 to 17.5. The car runs as well on the top end as it did with the 750 3310 Holley i was messing with and has just as good throttle response on the bottomend as the 600. Interesting feature of this carb is the primary venturis are smaller than the secondaries even though the throttle blades are all the same size.