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Getting my ADII165 installed today. What pressure do I need to run it at? I have heard of 20+ on a max effort tune, but that CAN'T be good on a CP3??? I have even had reputable guys tell me do not run over 10-11 ever.

Also, does anyone have pictures of the bottle test? Preferably LMM. I'm not to mechanically inclined and I was looking around yesterday and I'm not sure what to pop off, cap, and run a line from? I'm hoping I don't have to shim.
 

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I daily drive mine at 28 PSI.
 

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did not know that.. thx brian.

what would be the benefit of running above what the lb7/lly can do?

/asking. :beer
 

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I run mine at 17 psi for daily driving and 25+ at the track. The LBZ and LMM can run upwards of 40 psi with no detramental effects bc these trucks do not have an FICM like the LB7 and LLY which goes haywire with any pressure over 15psi.

As for the bottle test look at PPE's website and familarize yourself with the FPRV then go to your truck and locate it. You will see a horse shoe shaped black piece of fuel line going from the fuel rail to a distribution block. Move the hose clamps so you can pull the hose off the barb near the fprv. Gety a 1/2" bolt to screw into the line or it will pour diesel with a lift pump, then hook your length of fuel line to the fitting you pulled the line off. Place a bottle somewhere safe away from rotating assembly and put the hose in it and go beat on it for a few WOT pulls and check for fuel.
 

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Brian is correct.

LB7 and LLY 8-10 psi. If you have an LB7 or LLY and even running at 8-10 psi makes it lope you could have a FPR problem.
 

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It is an LMM, stop trying to confuse people. You can set it anywhere betwean 0 and 40psi on lbz and newer. I like around 20 for Daily Driving.
 

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The more you turn it up, does it get much louder? Just wondering? Chris
 

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^^^A little but not very much.
 

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so if there is no harm in running at a higher psi, why would a guy want to set it lower for daily driving and higher for racing? just asking. should i crank mine up while sled pulling? (max effort tune on an lbz)
 

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Idk, i'd like to see some proof that cranking it up higher for racing provides a power gain.

W/o having larger injectors and pump work i doubt higher pressure will get you more HP.

There are a very small handfull of truck out there running more than 40 psi on a duramax and they actually need it. Oh and not all of them are LMM or LBZ's ;)
 

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so if there is no harm in running at a higher psi, why would a guy want to set it lower for daily driving and higher for racing? just asking. should i crank mine up while sled pulling? (max effort tune on an lbz)

you want to get out, and under the truck to turn it up?

haha.. i don't.. :D
 

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you want to get out, and under the truck to turn it up?

haha.. i don't.. :D
haha. yeah, as long as its not hurting anything to daily drive it turned up then i might as well. i got plenty of other prep to do on sled pulling day. don't need one more thing to forget
 

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haha..

I'm down to find out what the difference is between DD'ing at 10 PSI vs 30...
 

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Idk, i'd like to see some proof that cranking it up higher for racing provides a power gain.

W/o having larger injectors and pump work i doubt higher pressure will get you more HP.

There are a very small handfull of truck out there running more than 40 psi on a duramax and they actually need it. Oh and not all of them are LMM or LBZ's ;)
I doubt most LB7 and LLY owners want to reroute their return line through the FICM.:thumbsup

I see a slight improvement in maintained rail pressure with it over 20psi but it shifts diffrrent so I drop it below 20 for daily driving. The improvement isn't very much but it is better.:rockin
 

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Is one full turn 8 PSI? How much is a full turn?
One full turn is 10 to 12psi, but if you want to dial in anymore you need a gauge.
 
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