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Discussion Starter · #1 ·
i believe i am in desperate need of another fuel pickup. im running robs twin tuning and i cant seem to hold rail pressure on the hot tunes. i have a ppe lift pump but still using the stock pickup in the tank. im pretty sure this is a stupid question and im hoping this will be my problem because it would be an easy fix. it should be alittle over a 600hp tune so i should definatly need another pickup correct? i never knew how much the stocker would flow. so will it really make a differnce and help my problem (asking people that actually have done the mod and seen the difference)? another question, instead of spending $200 on a ppe one, has anyone ever made their own? it seems like it would be really easy to make. just a couple of AN fittings and some fuel line... :confused: maybe cost $50..? i know some of you are going to tell me to get some data logs and send them to rob to double check, but i cant do it right at the moment and if a pickup will help either way, id do it anyway :cool: cant hurt, right?
 

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Its just a worktruck
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The PPE pickup for the LBZ is only 80 bucks. ANd once you see it in person you'll understand why it makes a difference. Maybe your lift pump needs turned up a little bit as well.
 

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AKA treyfox11
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how much is it dropping been watchin mine too
 

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AKA treyfox11
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damn havent even thought of that chris
 

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NewEST Spinny Thinggg
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do you have a fuel pressure gauge...test at the cp3 if the lift pump maintains whatever pressure you have it set to going into the cp3 then its not the pickup...also is your pump stock pressure or turned up?
 

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AKA treyfox11
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dang its 2 in the mornin what you want from me?????lol:rof:rof
 

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Its just a worktruck
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Sorry bout that, back OT. :D

If you can get a fuel press gauge you can see exactly what is happening at full throttle. As long as you're holding 1 PSI in the line the next thing to check is CP3.
 

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AKA treyfox11
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yeah sorry
 

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Its just a worktruck
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Just a question....What is your FRP dropping to at WOT?
 

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Discussion Starter · #10 ·
everyone keeps saying about reading pressure but how do you see the gauge under the hood when your driving it :confused: and can you get me a link for this $80 pickup, the cheapest ive found is $165 shipped. as for the lift pump, yeah its stock setting which is supposed to be 12psi i think... as for pressure, on my hottest tune it usually calles for something like 26,600 to all but 27,000 psi and it usually only holds like 23-24,000 at wot
 

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NewEST Spinny Thinggg
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really you need to see what the commanded pressure is compared to actual...if its not the lp it could be in the cp3 or maby tuning (even though robs the shit)
 

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AKA treyfox11
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you have to monitor it with your efi scan tool pick your pids for fuel pressure desired and actual and then watch them as you drive or get a friend to drive
 

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NewEST Spinny Thinggg
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crank it up to 15 psi (max) and see if it still drops
 

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Discussion Starter · #14 ·
ive been told the cp3s dont like that much pressure and anything over 10-12psi is just harder on the lift pump. about the rail pressure readings, they are comming from my edge monitor. i dont have an efi live scanner, i wish i did :rof
 

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AKA treyfox11
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ah hah thats where i got you , dang i don't know how your gonna see then and yes i don't know about that much psi to the cp3, i think it makes them surge or something
 

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Its just a worktruck
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everyone keeps saying about reading pressure but how do you see the gauge under the hood when your driving it :confused: and can you get me a link for this $80 pickup, the cheapest ive found is $165 shipped. as for the lift pump, yeah its stock setting which is supposed to be 12psi i think... as for pressure, on my hottest tune it usually calles for something like 26,600 to all but 27,000 psi and it usually only holds like 23-24,000 at wot
You mount the gauge in the cab.
Your rail pressure is fine. It will NOT stay constant unless you have dual fuelers. If it drops under 21K at the shifts then you have a problem.

The pickup for the LB7/LLY is 165. The one for the LBZ is only a piece of hose and the pick up. You dont need to cut the sender to install the AN fittings.
 

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NewEST Spinny Thinggg
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run a check valve return in the lines that way it doesnt build extra pressure and mess with the cp3...although it seems lke volume should be more an issue then pressure but it may need the extra pressure to feed the cps at WOT
 

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NewEST Spinny Thinggg
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IDK for sure...but if I had to guess a 85% over dragon fire cp3 with dual feed lines would help:D
 

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AKA treyfox11
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You mount the gauge in the cab.
Your rail pressure is fine. It will NOT stay constant unless you have dual fuelers. If it drops under 21K at the shifts then you have a problem.

The pickup for the LB7/LLY is 165. The one for the LBZ is only a piece of hose and the pick up. You dont need to cut the sender to install the AN fittings.
i wondered if that was a problem or not mine stays right at 24,000 at wot even through shifts so i guess i am fine till built motor and dual fuelers:D
 

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Discussion Starter · #20 ·
i dono what it is but it just seems like it shouldnt be that low. you can actually feel the truck stop pulling when it drops and its not as fun :rof. i just want to do everything i can, short of dual fuelers, (although in not ruling that out yet either lol) to make it stay up there.
 
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