Number Of Barrels: 4 CFM: 390 Flange Style: Square Bore Choke Type: Electric Finish: Zinc Dichromate Fuel: Gasoline Fuel Inlet: Single Calibration: Six Cylinder Engines Secondary Type: Vacuum Vacuum Secondary Allow Use On Wide Variety Of Vehicles. Compensate For All Vehicle Weights, Gearing And Transmissions To Allow Smooth Opening Of Secondary Power Valve Blow Out Protection Eliminates Blown Power Valves 100 Percent Wet Flow Tested Electric Choke. Single Feed Fuel Inlet Calibrated For Excellent Street Performance. Universal Calibration For Easy Bolt-On Performance