I installed a zenith carb off a 1957 gmc 270 on my 261 chevy... runs great and have decent mileage. I still have the original larger 261 Rochester but it didn't perform as well ... even after a rebuild ... its the larger Rochester made for the 261..
Old Truck addict 1950 chevy 1 ton napco 1956 gmc 1 ton dually napco 1954 chevy 3/4 ton napco 1957 gmc civil defense napco panel