255 LPH Returnless Drop-In Retrofit EFI Fuel System w/Hydramat Supports up to 550 EFI or 700 Carb HP (HP Rating @ 60 PSI at 13.5 Volts / 10.4 AMP Draw); Are you interested in an EFI retrofit kit, but just can't get past the complication of the fuel system? Holley is proud to introduce their Universal In-Tank Retrofit Fuel Modules! Available in return and returnless versions, you can rest assured Holley has the solution you need for your EFI fuel pump woes.