Can you utilize PWM with a return line?

[Markuli]

Hi everyone,

I plan to install an FiTech Meanstreet 800 on my 406, along with a new Boyd tank which comes with an Aeromotive 340lph in- tank pump. I want to utilize the PWM function on the FiTech to go a little easier on the integrated fuel pressure regulator. Is there any downside to running a return line in my fuel setup if I'm also going to use PWM?

[Joyridin]

The whole point of the PMW is to not use a regulator. It varies the pressure accordingly so a regulator is not needed. If you put a regulator inline, it will probably not do anything depending on where you have the regulator set and may actually reduce flow.

I would either run the constant flow with a regulator, or the PMW without one.

[biketopia]

Exactly what Joyridin said, one or the other, not both. Remove the internal regulator and use the PMW to set fuel pressure or, remove the internal regulator and install your own regulator and return line and run the pump at constant flow. If the FiTech is anything like the holley snipers, I wouldn't trust the internal regulator to hold up long term.