I'm having some problems with my fuel pressure - stock fuel pump. My in cab gauge from one second to an other started to jump like crazy, it's almost like sending me each injectors spray with a widely jumping hand on the gauge. Without the engine off/ key on the pressure is at 65psi - with BB mod, but as soon as I crank it up, it's jumping - more like vibrating. It's between 55-65 at normal driving, but when I step on it hard - with XtremeStreet program, it is between as low as 35 and 55. I can't get a good reading, because it's all over the place. I also noticed power loss at this pedal to the floor situations, while it still feels really powerful on the low-end. The power loss might be just my imagination, but I'd swear that I lost high end power. It just doesn't feel as wild as it was before - even with 32psi boost on the gauge.
Now to get to my point, I'm planning to do the upgrade on my fuel system really shortly, because this thing is driving me crazy, and I'm going to get the Airdog pump - after Nccpartsman positive feedback on it - and also get the ITP regulated return kit too. The RR kit is pretty much an easy to choose - since they offer one kit for the 6.0.
But I do have a question about the Airdog. On ITP-s webpage, the Airdog is described as a lift pump, being like a pre-pump / water separator to get clean fuel to your stock fuel pump, while nothing like this is mentioned on an other sources page .
Here are the two pages:
http://www.itpdiesel.com/store.php/products/AirDog
http://www.xtremediesel.com/pureflow...temfp1502.aspx


This is confuses me some, since I just want to throw the stock pump away, I need a good, reliable fuel source for my truck.
Any advice would be really helpful, I'm curious about your setup guys, what you use, what would be a good kit for my truck, and I'm kind of sold on the Airdog, but Airdog, or Airdog II?
Thanks

 

i've read the the air dog II is more powerful and quieter... i have a FASS though so i don't know first hand.

 

Airdog is a low pressure lift pump and supplies the stock fuel pump like a helper pump. The ADII is a stand alone high pressure pump. You're definitely running out of fuel. You won't find much on the ADII anywhere, but I'd be happy to answer any questions. It's not even on the pureflowtechnologies website yet. You will have to leave your stock pump in place, which is actually a good thing. The return line to the tank you never have to unhook. It's a really slick install when you haven't previously butchered your fuel system for another aftermarket install. They do come in two different styles. One with adjustable pressure, one with set pressure. You should go to the website and give them a call.

 

I'm not sure about more powerful, as it uses a 20A vs a 30A fuse like the FASS does, but it's definitely MUCH quieter than the FASS

Dcaddi--did you notice if you were getting a larger TOTAL fuel pressure drop with the BB mod and does it eventually recover? I am thinking that by raising the pressure (I did it also) that you are actually getting LESS fuel to the injectors. I haven't had time to test it with my ADII yet because of rain, but I'm going to drop mine about 5 psi and see how much it drops.

 

Thank you guys for the response!
So, the ADII is a stand alone fuel pump - like you said, but I have to leave the stock pump in place? Is it simply just not used, or is it still an active part of the system?
My issue makes me believe, that something is not OK with my stock pump - even though it still works, so I really hope that I can just replace it with a more efficient pump, and not just feed it with an other pump.

 

I have the Airdog II 130/75 and it is GREAT.
I was getting a fuel psi drop to 10-15 at WOT so I had to do something.
Yes you leave the stock HFCM in place and all it does is return the fuel.
From my understanding you do not need a RR kit with the Airdog II because it already has a regulator in it.
I have the ITP kit because I did it before the pump. The ITP kit is great but it is a PIA to put in.

 

I have not heard about this. Does anybody else know anythign about this being correct. Because i bought a RR kit and am plannign on buying the airdog II but if i dont need the RR kit i will try and sell it, I havent even taken it out of the box yet. Also where did you guys buy the airdog II, i have been trying to find it but everywhere says that it still hasnt come out yet for the 6.0

 

You don't necessarily need an RR with the AirdogII, but I already had one installed. I got mine directly from pureflowtechnologies.com Call and ask for Toby. Super easy install on a factory fuel system. Just make sure your tank is empty as you'll probably want to drop it a little to connect the lines and make sure you get the SN# off the pump before you mount it.

 

I got my Airdog II from XDP

 

Sorry for not being here the last 2 days, I just got back from the other coast.
I did not have a chance to check the pressure with and w/o the BB mod, because I've had that done before the FP gauge got installed, but my pressure loss was about 10 psi WOT compared to the idle pressure.
In theory the fuel pressure will be even if the pump is able to keep up with the fuel usage of the injectors, and the size of the fuel lines let enough fuel flow to the injectors. As you raise or lower the pressure - talking about 10-15 psi, you have relatively the same volume fuel compressed in the lines. If you see a large pressure drop at WOT, that would mean that some part of the system can not keep up the flow, and it robbs the volume.
As I understand, the ADII is a high volume pump, it's a 150 GPH at 5 psi pressure - as it stated by the vendor, but there is no data on higher fuel pressures.
I believe, that getting a relatively even fuel pressure in any circumstances would require replacing every single component of the fuel system.
Now I'd be happy to see a 5 psi swing at like 60 psi, but not more than that.
Will the Airdog II fit into that requirement?

 

The model # is 130/75 so I'm not sure of the flow on the AD2, but it's not 150@5psi like some of the stuff I've read on other websites. That sounds more like the Cummins pumps. I lowered my @idle pressure to see if it would compensate for the very large WOT drop I was getting. I initially had it set at 56psi@idle and dropped to 40psi@WOT. I backed the regulator on the pump out 1/2 turn which dropped me to 51psi@idle and it only drops to 45psi@WOT. I'm not entirely happy with it, but I'm not absolutely sure of the accuracy of my incab gauge either. The manual gauge on my underhood regulator is 13psi higher @ idle than my incab autometer consistently.

 

I have the 130/75 and it is set at about 65 psi. I see a 4-5 psi drop at WOT with Eric's ex-street tune. I also do have a ITP RR kit so the fuel lines are larger.
I did the RR kit before I got the Airdog II to help with my psi dropping to 10-15 psi. at WOT but it did not help that much because I think my stock HFCM was week.

 

dcaddi2 - great thread!

npccpartsman - appreciate all the good info!

 

Question here- if you keep the stock HFCM and add the AD2 I would assume you would still need to keep a good filter in the factory HFCM? I haven't researched the AD2 but I think I saw pics of one and doesn't it have a filter and a water separator side by side? I might be looking into this for a fall/winter project, depending how the funds are.

 

The Airdog II has a filter and a water separator so you do not need to change the stock filters.
With the Airdog II the stock HFCM stays in place and your fuel return goes through it but that is all.
When I put mine in I put a piece of tube with a bolt for a plug it the end on the stock HFCM fuel out let to stop any stuff from getting in.