I've owned my Dodge for over 4 years now, and have upgraded the lift pump, which is the raptor 100 gph on the side of the block, edge ez, 4 inch exhaust, and I believe it has at least 60hp injectors that were installed by the previous owner. I am at 400 rwhp now, tested at the hunting for horse power up in cda. My question that I am asking, why is my fuel pressure dropping down 5psi at WOT? I have spent many hours trying to find information on this, and its hard to get a definite answer. the Diesel mechanic I take my truck to says its normal, but I know its not, especially since my truck will start to stutter if I let off the pedal after stomping into it for to long( by no means do I drive the truck aggressive, I drive it like an old man, like my old man lol)  I want to upgrade my fuel lines to half inch from the tank to the lift pump, including fittings. but when I look online, I'm only finding the big line kit from the filter to the injection pump. Any advice would be much appreciated. I'm not looking to start a proper fuel psi forum, as I know its been beat to death.

 

15 psi at idle, 5 psi at WOT- doesn't seem normal. I'm on my second raptor 100gph -----this is my first post, let me know if I'm doing anything wrong.

Edited March 10, 20178 yr by Alexio Auditore

Yeah I can't speak for the new 4th generation pumps. I know the raptors are junk I've got one at the house that ate the pump shaft with just the rubber seal. Weird?! I'm not fond of the adjustable fuel pressure regulator. I like the old spring and check ball they work the best. I know @Me78569 has a Pureflow pump that has zero issues. Might ask Me78569 about his...

I have a pureflow pump from the patent owner of the airdog stuff.  Different companies now.  I am not sure if airdog ended up using the pureflow design or not, but my pump is good. 

 

I would however recommend FASS still given the run around I got from Airdog back in the day.

I had air dog 150, I now have fass titanium 150 and love it, but only have maybe 15k on it so not sure about longevity, but would still get that over new airdog. Still running original filters it came with.

There is always the mechanical option. I have the fuel boss and it has been problem-free since the day I installed it.

I have an AD II 165 for 7 years of so. I did loose the pump about 2 maybe 2.5 years ago and the sent me another no questions asked, Mine also has the adjustable pressure regulator and works fine. Had to reset a couple times when new and after replacing the pump. No other issues with it. Might go different if this one does not last we will see.

20 minutes ago, Hawkez said:

There is always the mechanical option. I have the fuel boss and it has been problem-free since the day I installed it.

Same here, 16-17psi at idle, dips a for quick second under acceleration, then 17-18 with some rpms.

20 minutes ago, Hawkez said:

There is always the mechanical option. I have the fuel boss and it has been problem-free since the day I installed it.

Same here, 16-17psi at idle, dips a for quick second under acceleration, then 17-18 with some rpms.

Whichever route you choose, the questions you asked will all be covered by the kit you buy. Filters can be purchased practically anywhere. I personally by passed the stock fuel filter with my FASS 150.

Why people buy these unreliable over priced pumps is beyond me. There are many many options available to put together your own systems if you are willing to spend the time.

In your spare time perhaps you would be willing to do an article 

1 hour ago, jlbayes said:

Why people buy these unreliable over priced pumps is beyond me. There are many many options available to put together your own systems if you are willing to spend the time.

 

jlbayes ...Options are limited aren't they? FASS or AIrdog, or mechanical with fuel boss?

 

 

Aeromotive and fuel lab as well if you want the boxed fuel systems.

Wasn't it CumminsDog who had all kinds of issues with one of those suppliers and ended up with a FASS?

Yes, fuel lab. Due to the "pulse" on key on. Their controller would not pick it up and then would lock out the motor once engine was running. 

The mechanical pump looks like a good idea. But either case I need to replace the lift pump. They use the lift pump on start up right CTcummins24valve and Hawkez?    

 

Come to think of it, I have a warranty on the raptor, if I buy the mechanical set up the raptor would be used for only a few seconds for start up.    Still is guna be at keast 600 dollars whatever way I go. Do the belt driven ones have a return line also?

1 hour ago, Alexio Auditore said:

The mechanical pump looks like a good idea. But either case I need to replace the lift pump. They use the lift pump on start up right CTcummins24valve and Hawkez?    

 

Come to think of it, I have a warranty on the raptor, if I buy the mechanical set up the raptor would be used for only a few seconds for start up.    Still is guna be at keast 600 dollars whatever way I go. Do the belt driven ones have a return line also?

You can, with a hobbs switch. Hobbs switch only powers on when fuel pressure dips below a certain psi. Right now I have the carter pump disconnected, just running the fuel boss. Only connect the stock carter pump for filling the fuel filter housing during a filter change for me. 

3 hours ago, Alexio Auditore said:

Do the belt driven ones have a return line also?

Yes, it does.  The fuel pressure regulator is in that line and they have it returning the fuel by way of a t-fitting in the filler neck hose. 

 

2 hours ago, CTcummins24V said:

just running the fuel boss

I run the fuel boss the same way.  An electric fuel pump is installed but the fuse is pulled for power to terminal 30 of the relay.  This keeps relay triggering power flowing from the ECM to relay terminal 86, the electric fuel pump doesn't run and no fault code p o230, or p0232 is set.  

Are there anythings to be worried about going the mechanical way? How long have some of you been running mechanical? Any issues?

Carrying a spare belt is the only issue I am aware of on the lower pressures the vp trucks need.

8 hours ago, Alexio Auditore said:

Are there anythings to be worried about going the mechanical way? How long have some of you been running mechanical? Any issues?

I have had no issues with my fuel boss.  I have my stock lift pump still hooked up and it is only used to prime the system.  I do carry a spare belt under the back seat.  When I bought mine, Richard at GDP said he has 100K+ miles on a belt.  I've never heard of one failing, but I assume there are stories out there. My pressure is solid at 17PSI. It doesn't go up or down much at all from that. 

10 hours ago, Alexio Auditore said:

How long have some of you been running mechanical? Any issues?

   I installed mine just over 4 years ago (5/2013) .  Fuel pressure was 17 at idle and 19 going down the road when first installed then went to near 0 a few days later.  I found a bit of debris from the installation keeping the fuel pressure regulator stuck open.  It's e-z to open the regulator and clean out or adjust fuel pressure if there is a need for it.

   

    I keep a spare belt under the back seat but there is also that spare fuel pump in the fuel system.  All I need to do is in stall the fuse.