Do you only use a certain one depending on what your management applications are? Or is it generally better to use one over the other? I'm planning to run stock boost on a Greddy kit...so I'm only going with a fmu setup for now. Will an intank like Walbro 255lph be good with that? What do people recommend and why?

 

If you are using an fmu setup than use the inline pump. Inline pumps can produce higher fuel pressures such as like around 120psi + with stock injectors. This increases the duty cycle of the injectors. The walbro's can't produce high fuel pressures such as those. They are generally used with larger injectors. Hope that helps.