The DW400 fuel pump has a quoted flow rate of 415LPH. The Walbro 525 has a quoted flow rate of 525LPH. So why do DW customers make just as much power on the DW400 pump as they can on the W525? The short answer: PRESSURE. Not all is equal when quoting flow rates. The DW400’s 415LPH is achieved at 40psi, while the Walbro 525’s 525LPH is achieved at 0psi. This is like comparing one car’s crank hp to another car’s wheel hp. Deatschwerks pumps are rated at 40psi because that’s the minimum operating pressure of an EFI fuel system. High performance forced induction EFI engines actually experience much higher pressures. High load and high boost = high pressure and that is where you want your pump to be performing at its best. So what happens when you put these 2 pumps head to head? We sent both to RC engineering for unbiased 3rd party testing. The charts tell the real story. Thanks to Bosch’s high torque 29mm motor, the DW400 flows more at higher pressure and draws fewer amps in the process.