The Nov 2018 issue of Car Craft has a very interesting article called "LT Engine Swap Shop" (Pg 36 by Jefferson Bryant). No - I'm not changing brands ... but I have been very interested in PWM fuel pump controllers that sense pressure at the fuel rail and then drive the fuel pump just enough to maintain pressure and feed the engine (no return - no tank fuel heating).

On page 38, they discuss the LT fuel system and GM Fuel Pump Controller. I have an in-tank Aeromotive Eliminator Fuel Pump and the Aeromotive PWM Fuel Pump Controller. But this controller senses RPM and PWM's the pump based upon the tach signal. That's good but there still is a return line and fuel heating. RichN always recommends a return line system for EFI applications and he's never steered me wrong but I wonder what he has to say about these pressure sensing PWM fuel pump controllers? All the new factory cars/trucks seem to have gone to returnless systems. The article says that you need the GM ECM to talk to the GM Fuel Pump Controller and I'm using the XFI so a hack for that would have to be figured out. My EFI map was learned/tuned on the dyno at 50psi fuel pressure. The LT System looks like it is set at 60psi so that would have to be remapped or figure out how to fool the controller to think it is 60 psi when it really is 50 at the fuel rail. I think that a PWM Fuel Pump Controller that senses fuel pressure and modulates the pump to supply fuel without a return might be the way to go. That and very well insulated fuel lines and fuel rails to keep the heat out of the fuel as much as possible might make for an optimal EFI fuel system.

What do you guys think?