Engine/Transmission (1998.5 - 2002) fuel return line upgrade?

[samsonite01]

Just finished big line/lift pump relocation kit from vulcan. Going to put a bdp sump on next and eventually a fuel water separator/cat fuel filter dual setup. I wonder if up sizing the return line would do any good for the system? Maybe a -an 1/2in style fitting off the back of the head then cut the hard line at the pump return and hack on a fitting to accept 1/2in line. Then 1/2in back to the tank. Would it make the lift pump run harder or smoother? Would it help with fuel temp? Would it help th vp44. I thought t read that 70* of the fuel should return to the tank in order to take heat off the pump. Or am I going overboard? What kind of return systems do they run on high hp trucks? Tryed a search...they don't work for me...maybe I'm tarded or somthin.

 

[MLee]

Most run a FASS system to get away from the stock lift pump and a more equal fuel pressure plus better filtration.

 

[DieselRyan]

70% of fuel is used to cool the injection pump and is returned back to the tank. Putting a larger return line will most likely not give you any major improvements. It may relieve some of the pressure build up in the injection pump. High horsepower trucks is another subject. Fuel return styles can vary depending on HP levels and racing preference. In my opinion, the stock return will be fine.

 

[JR]

It really won't make a difference, the overflow valve on the VP is what determines the amount of fuel returned. The OEM lines are sized more than adequately and do not cause any restriction or pressure issues.


The best thing you can do to improve the lift pump reliability is move it to the frame rail (which sounds like you did). There is a good reason why Dodge only mounted electric lift pumps on the engine for 4 years, because its a horrible place to put them. Heat soak from the engine and engine vibrations shorten the life span incrementally especially if using a mediocre lift pump such as the OEM Carters or Air Dogs. Pumps are also designed to push not pull fuel, so putting them on the engine makes no good logistical sense. Vulcan Performance (website) makes relocate wiring kits complete with relays for those not comfortable building their own. Another bonus is the kits draw power from the battery not the ECM. The OEM set up relies 100% on electrical requirements THROUGH the ECM, the relocate kit only relies on the ECM to trigger the pump.

Are you sure you want to do a sump on your tank? I'd be leary about running fuel lines that low, not to mention potential leaks.