Has anybody modified your fuel pick-up located inside your fuel tank? I have heard the pick-up screen located at the bottom of the plastic cylinder restricts fuel flow at WOT conditions. If you have done this can you explain what modification you did and state the improvements that you have seen by doing this.

 

A stock 3/8" fuel tank pickup will flow about 13 gpm with diesel fuel at a pressure ov 10psi (atmospher is 14.7). That's (13*60)= 780 gallons per hour. That's a LOT of fuel flow.

There's a STRONG possibility that you're not seeing any restriction from the pickup diameter. The screen itself is another matter altogether.

Justin

 

The trouble with the pick-up screen that it does more than just filter fuel. It also regulates the return fuel into the tank. When you have less than 1/4 tank of fuel during acceleration, fuel is at the back of the tank. So if you just have a pick-up with no screen you will have no fuel. I did a mistake by removing the screen as someone told me that this is a flow restriction. Yes it restricts flow but its benieft is that allows you to get recycled fuel into the pick up at lower fuel levels. The really sad part is that dodge doesn't sell this screen by itself and if you get some dirty fuel, your buying a entire plastic tube. Its price is $650cdn. I know that 3/8 will flow lots of fuel on the discharge side, but remember that this is the suction side and is under vaccum. Going to a 1/2 tubing will help reduce restriction. I have seen 1 psi gain by modify the pick-up at wot. I'm gonna try 3/4 and see as I have nothing to lose. I just wanted to see if anybody else has done this and wanted to see their results. Actually dodge should just put a pump in the tank like they do on gas engines. Everybody know those pumps last longer than the cummins(carter) lift pump junk.

 

Discharge and vacuum aren't really different, as all that matters is the difference in pressure. If you have a difference of 10psi, then it's 10psi, whether it's coming from discharge or from atmospheric pressure being 10psi greater than something else.

An old racer's trick is to hog out the tank vent line....ou can starve an engine for fuel if air can't get in the tank to displace the fuel that's leaving.

Keep us posted on your progress.

Justin

 

When I installed the Preporator,I did a lot of learning about the flow of fuel on my truck.When I first installed the Preporator I used the standered 3/8" line and used a primary lift pump to deliver fuel to the Preporator.What I found I had great pressure at idle 22psi but at WOT it dropped below 5psi.So I lifted the bed of my truck, and installed a 1/2'' bulkhead flarenut fitting into the sendunit assy, I took the filter assy. apart so I could run 1/2" copper pipe which I sweat together to the bulkhead flarenut.I choose to fabricate my pickup tube in the original sending unit assy. cause it serves as a baffle in an other wise open tank.After the install of the bigger pickup tube,I was able to get 20psi of pressure without the primary lift pump.at wide open throttle it dosn't drop below 13psi.I think two pumps and 3/8" line will work great to 500hp after that one needs to increase volume to the VP44 and install a larger suction line .Merv

 

Did you run a complete 1/2 tubing from the tank to lift pump, fuel filter and injection pump? I'm impressed that your getting 22 psi at idle on a stock lift pump. I have given up on the stock lift pump and I have bought a Fass pump. I havent installed it yet. I'm waiting on Dodge to put in a new injection pump so I can start with a new VP44 pump. The Fass system uses a 3/8 tubing. It has its own return line plus it uses dodge return as well. This thing must move fuel as the manual states that the truck has to be off during re-fueling or fuel spillage with occur. The pump is massive and looks very well built. The pump and filters probably weighs 30lbs.

 

Mike the 22psi was with 2 pumps in series.I did use is 1/2" inside diameter on the suction line and 3\8" on the delivery line I modifiyed the original pickup tube so that the Preporator would return the fuel back to the old suction line,so I wouldn't have that problem with filling it with the truck running.Merv

 

The father Charles Ekstam makes the Preporator and the son Brad Ekstam makes the FASS.Merv

 

If you are using the stock fuel lines and going through the lift pump you are defeating the whole purpose of the Preporater/FASS system. Get rid of all that junk and go directly to the VP44 with 3/8 line, nothing in between the Preporator and the VP44. It is a whole fuel system. Hooked up that way you will have one pound drop from idle to wot. The Preporator has enough volume and pressure to wash parts with it.

 

The Fass system will directly connect to the injection pump with 3/8 hose. It has its own fitting that connects to the injection pump. If you want 1/2 just use 1/2 hose. The only thing you use that stock is the connection in the tank and return line from the injection pump. The return from the Fass pump is dumped into the tank vent line. This pump must move fuel to cause fuel slippage during refueling. A good thing. I'm gonna try the 3/8 hose as supplied in the box, to give me a base line. From there I plan to play abit with different hose sizes and fuel pick-ups. All the different connection with hose clamps kinda scare me abit so I'm gonna get some custom made hoses with crimped ends made once I finished playing. A new toy.

 

What I was trying to say was when I first installed the Preporator I did try running the 3/8" fuel line first with a primary lift pump to assist the Preporator because I was using a small line.I then got rid of the primary pump and just installed a 1/2'' line from the tank to the Preporator.Which worked beautifully.

 

Maybe I just save time and just install 1/2 line all the way around. Thanks for the heads-up.

 

I had the impression from the post that you were running both pumps, guess I read it wrong.