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I have an AD II 165 and have it set per installation instructions (one full turn clock wise, this is supposed to be 10 psi). I am curious to know what the actual output pressure is. My Edge Insight only monitors rail pressure but I would like to know the pressure on the output of the lift pump. I am considering adding a gauge at the stock fuel filter bleed screw. I don't really want or need to put the gauge in the cab, it would be for setup purposes only. Anyone doing this or have any other suggestions? I'm a numbers kinda guy and just hate doing the "one full turn" thing...I would rather tune the pump based on actual pressure values. Also, what is the optium fuel pressure going into the stock CP3 pump.
 

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I have my regulator set to ~24 PSI. I have seen the gauges that screw onto the factory head but have never used one. I don't even have the factory filter anymore. I don't think the pressure is critical on our trucks, meaning 24+/- a few PSI isn't gonna make a big difference.
 

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How do you know it's at 24psi?
 

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I'm curious about this also. I'm throwing a p0087 code and turned my AD a half turn clockwise from the factory but dont know what psi it's putting out. I guess I better order up a gauge.
 

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I spoke to one of the AirDog reps and he told me you can pull a plug on the airdog itself to install a pressure gauge.


You can see in this picture where they have a hobbs switch installed.. this is where you can monitor pressure at. (not a ADII, but same plug location)
 

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How do you know it's at 24psi?
My rationale was if 1 turn from fully closed was 8 PSI then 3 turns from fully closed is 24 PSI!!!
 

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Mine came set from the factory at about 7 PSI.... used the gauge on the factory fitting under the hood to test.... I could get it to go down to about 3 PSI when I put my foot into it on my 160 HP tune.... i looked awesome driving around with the gauge/hose connected under my hood, sticking out by the wipers and being held down by the windshield wiper as I tested it. I cranked it up to about 14 PSI.
 

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My rationale was if 1 turn from fully closed was 8 PSI then 3 turns from fully closed is 24 PSI!!!
Thats pretty much dead on! I did three turns on mine and it was 26 psi at the filterhead.
 

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Thats pretty much dead on! I did three turns on mine and it was 26 psi at the filterhead.
Glad to hear, I didn't want to have to hook up a gauge.
 

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They should really add a gauge on the ADII. I have mine set at 3 turns and it is perfect for me. I have the 5PSI warning light, and it never comes on even during WOT max effort. I'm not pushing to much fuel either.
 

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Digging up this old thread I just installed a guage from the test port directly on top of the AD. It's a 1/8" NPT standard size thread too. Have to adjust it in a bit to see what it's at. Keep getting a change fuel filter warning at WOT if I'm there for more than about 3 seconds. Also getting a P160C and P166C code at WOT
 

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Still digging up this old thread read in the airdog instruction manual and it says 2 and half turns is 8-10psi and now y'all are saying 3 turns is 26? Can someone explain please
 

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I've found that anything much over 10-12psi and I start to get high rail pressure codes when coasting and it starts to idle like a cummins. Lots of people have found that the trucks don't like much more than 10 and you don't gain anything from running more than that if your fuel filter isn't plugged.
 

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Still digging up this old thread read in the airdog instruction manual and it says 2 and half turns is 8-10psi and now y'all are saying 3 turns is 26? Can someone explain please
Correct- according to the manual at least.



I still highly recommend running a gauge personally as the internal spring can relax causing the pressures to not be accurate.
 

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Thanks brokesmoke need to get me a gauge
 

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Thanks brokesmoke need to get me a gauge
Sure man-
FYI you can mount a gauge right on the AD- just use the pressure port to tap into.

 

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Thanks again, do you know what size fitting I would need there, I think I remember seeing it on a thread somewhere on here but can't remember what size
 

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Following - I installed the ad 2 165 and also followed the factory recommendation of 2 1/2 turns from full closed. Curious to know what my pressure is at. I've debated installing low pressure light but don't know if I will... Don't really want the industrial looking plate and orange light.. Although I could mount it down low instead of one plastic..
 
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