You don't really need a regulator if running a stock pressure mechanical fuel pump. If you are running an electric fuel pump, consider the Carter 4070. Rotary vane type, pressure runs 4 to 6 pounds, perfect for most all 1 bbls and two bbls, and it needs no regulator. The only issue is you have to put a filter in front of the pump, the pump uses the fuel to cool itself internally so the feed has to be clean or the junk will trash the motor. Otherwise extremely reliable.