more fuel options

[lariat 7.3]

hey guys, after installing the studs and springs and running my all out tune the fuel pressure drops to 20 psi. I already have a Frx and strictly diesel intank kit with pre pump filter. Can i just buy a secondary pump with a Y fitting and be good to go? Or do i need to do a full RR etc etc

 

[Crowerstroke02]

what fuel pump do you have

 

[Arisley]

You need a fuel system. Many options on pumps, but you need 120 GPH at least. And larger supply line and return line.

 

[Crowerstroke02]

imo i would build you're own fuel system not hard to do/ or buy a system from dynoproven

 

[lariat 7.3]

currently running a stock pump, im planning on adding a second stock pump, what i was asking is if i could just run a y fitting off of the pre filter line split it into the two pumps, then consolidate it back into one and keep the stock fuel bowl with the frx

 

[Crowerstroke02]

i personally wouldn't because of my preference, i would stick with a single pump either a walbro or 044 and just do a reg. return

 

[njjeep]

I got Marty's fuel system it works great and is easy to install.

http://powerstrokearmy.com/forums/showthread.php?t=36076


Sent from my iPhone using Tapatalk

 

[mandkole]

If it were me, I would first try the sump through 1/2" line to your 10micron, then the stock pump, then the 2 mic filter thru stock lines. You need that line volume between the pump and the tank, plus the sump gives enough head pressure to support the single pump. I think VRef got good results this way.

If you still cant maintain volume/pressure, then do the second pump with the 3/8" line up to the heads.

 

[4duggan]

I dont claim to know alot about this but there is no way I would have a put a set of injectors in prior to a fuel system. Not trying to be a dik , just my $.02

I second Marty's Fuel System , suggest you give him a call, my sons truck with Swamps 250/100's maintains 62 psi through entire range of the pedal.

 

[lariat 7.3]

lol, it sits at 62 PSI ALL DAY LONG unless i lay into it which is hardly and itll drop to about 50. So yes it is possible to run without a "full" system prior to injectors. Mandkole, you think i can upgrade the size of the lines pulling from the tank and draw straw and stock with a single pump without a sump?

 

[ToMang07]

lol, it sits at 62 PSI ALL DAY LONG unless i lay into it which is hardly and itll drop to about 50. So yes it is possible to run without a "full" system prior to injectors. Mandkole, you think i can upgrade the size of the lines pulling from the tank and draw straw and stock with a single pump without a sump?

^Says the guy seeing 20psi. LOL

 

[lariat 7.3]

hey, i dont drive around in my race tune all day long lol, hardly every leave my econo tune

 

[bigfords]

If it were me, I would first try the sump through 1/2" line to your 10micron, then the stock pump, then the 2 mic filter thru stock lines. You need that line volume between the pump and the tank, plus the sump gives enough head pressure to support the single pump. I think VRef got good results this way.

If you still cant maintain volume/pressure, then do the second pump with the 3/8" line up to the heads.

I still would say this may be a good idea, but I tried doing 5/8 line from a sump, to the 10 micron filter and my pressure still drops. I'm planning on adding a second pump eventually.

At what point do you need a bigger return line?

 

[ghohouston]

Fwiw, I had a bone stock fuel system with my 238/100's, with a new pump, it held 60 psi in the hottest tune I had... I'm not saying its the right way to do it, but it worked for me.

 

[lariat 7.3]

Fwiw, I had a bone stock fuel system with my 238/100's, with a new pump, it held 60 psi in the hottest tune I had... I'm not saying its the right way to do it, but it worked for me.

Lucky lol

 

[bigfords]

Fwiw, I had a bone stock fuel system with my 238/100's, with a new pump, it held 60 psi in the hottest tune I had... I'm not saying its the right way to do it, but it worked for me.

Was that with a Bosch or Walbro? I have a new Bosch, DI RR, and Dyno Proven Sump, and psi still drops if I put it to the floor after a few seconds.

 

[ghohouston]

Oem bosch pump. Hell, I may have gotten a freakishly strong pump, idk...

 

[TyCorr]

My buddy dane ran 238/80s on a bone stock truck for 25k miles. No issues. But he had a fuel pressure gauge. It made good power. He did eventually put a fuel system in and all the support mods.

He had a good 400+ hp setup for a long time with nothing else.

 

[V-Ref]

If it were me, I would first try the sump through 1/2" line to your 10micron, then the stock pump, then the 2 mic filter thru stock lines. You need that line volume between the pump and the tank, plus the sump gives enough head pressure to support the single pump. I think VRef got good results this way.

If you still cant maintain volume/pressure, then do the second pump with the 3/8" line up to the heads.

:whs:

I'm running a single SD Bosch pump fed by a TSD sump...holding pressure just fine.

 

[TARM]

I still would say this may be a good idea, but I tried doing 5/8 line from a sump, to the 10 micron filter and my pressure still drops. I'm planning on adding a second pump eventually.

At what point do you need a bigger return line?

Your return line size is dependent on the volume your pump is sending thru the line. Think at idle its using next to no fuel. Almost all of it is going back to the tank. The need to increase the size of the return line itself when it becomes a restriction to the fuel flow returning to the tank. The way you know this is when you can not control the max fuel pressure with the regulator. Say you keep trying to lower the full pressure by opening up the pressure regulator yet the pressure does not drop or stops dropping at a certain pressure which is at or not much lower than the pressure you want to run at. That is because the fuel is flowing as fast as it can thru the return hose and to run faster the pressure has to be higher. Thus the return hose because what is controlling the min pressure in at least a low fuel use state.

A every easy way is to always make the return line the same size as the feed then there is no way it will ever be the restriction. But normally a 3/8 line is usually plenty.


Unless you are pushing serious HP no way it will need more than 60-70 GPH. Two dual stockers or one 044 is plenty for at least 600 HP.

As the fuel lubes the barrel and plunger any drastic fuel drop is a bad thing and if severe can ruin injectors.

IMO go ahead and do a full RR. I would always do the tank mod even if I had a stock motor and fuel pump.

The reason you can not simply add a second pump on with a couple Y connectors is the PU and feedlines will likley create enough resistance and over work the pumps and end up burning them out.

There are almost countless ways from basic to complex that you can build a fuel system. I would stick with something basic but do a full fuel system. You can use the OEM feed line as the return to save some money. But at a min I would have a pick up pre filter water sep pump post filter and then Y up top each head. Y out of them into the return line.

There are all kinds of threads on here for fuel system builds. Pick one and follow it. I know I have put a number of them up with part numbers etc as have others from basic to wild.