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fuel pressure & rail pressure

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Old 06-30-2012, 01:47 PM
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Default fuel pressure & rail pressure

i have a question about them both, i know i need a fuel pressure gauge because A: i need it and B: im getting a airdog 165. what size fuel pressure gauge should i get and how much fuel pressure am i supposed to have??

Rail pressure.. what is that? do i need a gauge for that as well? and if so what size gauge should i get for that as well.

thank you for your help, im new to this hobby and im learning more and more off of everyone on this site you guys are awesome.
 
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Old 06-30-2012, 04:30 PM
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I'm running 20 lbs fuel pressure w/ no issues.

Fuel pressure is what's before the injection pump, rail pressure is after. Too much, and your damaging injectors. Too little, and you have a no start or lack of power condition. Same goes with fuel pressure. Too little, and your starving the fuel injection system, causing damage. The AD165 puts out more volume than pressure because when you have an extreme demand for fuel to the engine, it will keep up.
 
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Old 06-30-2012, 04:31 PM
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30 psi fuel & should idle 10-20 psi.
30k rail gauge? The factory rail psi is 25k-26k max before your rail plug pops which saves your injectors! That's the psi going to your injectors!
 
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Old 06-30-2012, 07:50 PM
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On a note: If your driving through a lot of stop or yield signs, leave it in a gear where you can roll to the next one and not shift. I leave mine in 2nd (auto) so my RP doesn't spike to 20,000 psi.
 
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Old 06-30-2012, 08:28 PM
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it says you have a 01 cummins. if so you dont need a rail pressure gauge
 
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Old 06-30-2012, 08:47 PM
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right on guys thank you much for the information, so am i good with that airdog 165? or should i get something smaller? i dont have injectors now but i will get 150hp injectors in a few months
 
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Old 06-30-2012, 09:01 PM
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Originally Posted by dolla_hite
it says you have a 01 cummins. if so you dont need a rail pressure gauge
He's right^^^
I screwed up, that info was for a 3rd gen!! I didn't see that you had a 01!
 
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Old 07-01-2012, 01:55 AM
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yeah that was my fault for not putting what i had my bad brother
 
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Old 08-22-2012, 07:53 PM
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I have a 04 cummings with 412000 miles just installed new injectors and a air dog II , I am having to much rail pressure at idle. 20k should be 5600 to 6000.
Engine extreamly loud any Ideas????
 
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