ATOMIC EFI 2 MASTER KIT Direct replacement for common 4-barrel carburetors with 4150-style (square bore) flange Master Kits Includes a complete fuel system external fuel pressure regulator preset to 58.5psi, 20ft of 3/8" EFI Rated Fuel Hose, Fuel Pump, Filters, necessary hardware and bulkhead fitting to return fuel into the tank! NEW Throttle Body Flows 865 CFM and features 1" Throttle Plates NEW Booster design offers superior fuel atomization NEW ECU is 100% incorporated into the throttle body no separate Power Module to mount NEW and Improved Calibration Wizard Answer a few simple questions about your engine and it creates the base map, then starts tuning on its own! NO laptop required! NEW High-Resolution, Full Color, 3.5" Touchscreen for Initial Setup, Tuning, and Gauge Displays NEW Optional Laptop Tuneability Ideal for fine tuning and unique engine combinations or for Boosted applications up to 21.5 PSI IMPROVED Built in Nitrous Cont