Engine/Transmission (1998.5 - 2002) Fuel Flow Rate

[Big-D]

I'm in the process of making my stock lift pump a pusher by moving it next to my fuel tank. In so doing, I'd like to add a fuel filter between the tank and prior to the pump, but I cannot find the required fuel rate for my '99 system. I will also be using the stock filter, which I understand is 10 micron, but the flow rate is not listed.



Can someone enlighten me as to the proper flow rate so I can purchase the right spin on filter?



Thanks in advance!

Dave

 

[Ncostello]

Hey Dave. I cant remember if we talked about that or not... but I am fairly certain the system was 45 GPH or around that. I'd have to go back and do a bunch of looking but that number really rings a bell when I recall everything I've read. I dont remember who posted that or where... but I do remember the user was very experienced in their work and research.



Now that number was what the lift pump was pushing through at operating pressures. I contacted Fleetguard and they sent me a their product sheet (word document format) of the filter specifications. Lots of data there about the filter (2 pages worth including stuff like G-Force ratings that would make it come apart) but I do not recall them showing any flow rates because it was all pressure dependent. But I'll dig that out and look again cause it should have been listed for some standard pressure. I just remember being disappointed because I got those sheets specifically to do what your doing.



I went with the Stanadyne FM100's which are good for 90 GPH. Seems like I recall most Racors that would fit down there in the 40-50 GPH range.



That 10M rating on the stock filter was at the high percent filtration. It showed the filter doing the smaller micron contaminates but will less efficiency.

 

[Big-D]

Neil,



If you can look those figures up for me I would really appreciate it. Every filter sales person I have spoke with has had a different opinion about what to use. If I know for certain what the flow rate should be I can purchase a filter accordingly. My worries center around flow and micron together for it seems they go hand in hand.



I have written on the Northwest Bombers site as well and looking forward to hearing what the experts have to say over there. I am surprised at how many guys have completed this modification already. Makes me feel as though I've been in the dark ages.



I shall await your response and thanks again Buddy!

Dave

 

[rfcom]

Let's say you were going 100 mph and you got 10 mpg. You would be using fuel at the rate of 100/10 = 10 gal per hr. I heard somewhere that 70% of the fuel flow was returned to the tank. To take a worst case, say 50% was returned. This means the flow through the pump would be 20 gph. Add a 100% margin and a 40 gph filter will work just fine. Of course, these numbers are ridiculous. The actual flow rate would be much less.



Jim

 

[Gary - K7GLD]

Seems to me the test mentioned above was done at Diesel Dynamics, using a test flowmeter and involved various changes in fuel lines and power add-ons to monitor fuel flow as fuel delivery/lines was improved, and power levels on the engine increased - it was found that flow thru the VP-44 maintained a steady 45 GPH *REGARDLESS* of fuel delivery, and the power levels, at least as far as they went with their test at that time - the thread is on this board - something like "fuel lines and things" as I recall - I'll look for it and post a pointer if someone doesn't beat me to it...



MY conclusion from that test, was that going to lots of expense and trouble to put in larger pump, lines and fittings, might give you a warm and fuzzy feeling, but do precious LITTLE to benefit the VP-44 or Cummins - at least up to 400-500 HP...

 

[Gary - K7GLD]

Here's more reading on the subject - especially note posts made by "Mopar Muscle" starting about halfway thru...



https://www.turbodieselregister.com/forums/showthread.php?s=&threadid=11672&highlight=lines+and

 

[Big-D]

Gary - KJ6Q



Your input is well received and thank you for writing. I am hopeful you can find the thread mentioned for I cannot. My desire is to work with both the lift pump and the VP44, thus my need to determine the proper pre-filter to purchase.



Another thought has come to me regarding flow rate. If all electrical pumps are rated at a designed pressure and flow rating, I wonder if Carter would provide me with their specifications for this pump?



Secondly, lets assume for sake of argument, if our lift pump does produce 45gph (unrestricted) and the stock filter restricts this rate by some unknown value and there is also a loss due to line flow restrictions, how much actual flow reaches the VP44? My guess is something much less than the rated output flow of pump. Perhaps that is why the return line to the tank is smaller than the supply line.



I don't wish to go overboard in finding a pre-filter and perhaps Baldwin can help me on Monday when I call them for the flow rate of their filter in the stock canister. I simply don't want to relocate my lift pump to the rear and restrict it once again by making the pump draw vs. push because I didn't use a filter capable of allowing proper flow.



Thanks to all who care to enlighten me.

Dave

 

[Gary - K7GLD]

Already done above - here's the pointer again - get ready for LOTS of excellent reading!



https://www.turbodieselregister.com/forums/showthread.php?s=&threadid=11672&highlight=lines+and