Thought Id take a poll to see what carburetor everyone is using on their series truck and what kind of fuel economy and power youre getting. Ive used both Rochester and Webers. Got 20MPG with my Rochester on my series 3 (with 15 wheels). Im currently running a Weber ICH on my Series 2a. Both were set up with Pertronix electric ignition. Not much power on my current rig and fuel economy is definitely less than 20MPG with 16 tires.