I ended up running 2 Modified pumps and still lose pressure at WOT. Do I need to do something to the Banjo bolts or something? It just seems the pumps cant pump it in there fast enough.

 

You must have a clog, kink or other problem inbetween the tank and engine that's restricting flow.

I know several folks pushing 600 hp with the stock delivery system no problem.

 

There might be some kind of clog or something but I sure dont know where it would be.

I am now thinking of putting in a more performance type of fuel filter, Can someone tell me what the little line is for that runs from the injectors back to the filter? Also When you put that remote filter bracket on that Cummins sells where does that little line go?

 

The small line is the return from the injectors.
Besides returning fuel it also keeps the fuel in the filter warmer which helps with gelling.
My understanding is the small line must return to the pressure side of the lift pump, returning it to the zero pressure return line messes things up.

 

So would I be safe to Tee it (Jector return) into the pressure feed from the electric pump?

 

Absolutely