suggestions rail pressue

LBZMIKE

New member
Nov 15, 2014
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colorado
Hello all first post here so here here goes got a 06 lbz with 118000 miles 2 monthes ago with plans of 600hp so i have got a 4 inch exhaust edge evolution on 100hp tune transgo jr and i just put a race valve in as mine was leaking and i also ported the pressure side of the cp3 and rail ...now it has issues with rail pressure i punch it qnd it hits 26000-27000 psi on both desired and actual but actual drops to 12000-13000 in 2-3 seconds i have a fass 150 on the way but what else could it be i will be deleting the factory filter setup as well

Thanks in advance to all
 

hondarider552

Getting faster
May 28, 2008
10,627
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36
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Arizona
you totally started with the wrong combination of parts man.


put that shit back to stock fuel system wise and start over.


I have 100% stock fuel system in my LB7, stock pumps, stock feed lines, stock hard lines, FPRV and made 1000hp.
 

LWATSON

future trans limpers
Jul 30, 2008
2,587
1
36
55
Scotland Neck NC
I'm no where near the power hondarider is but I also have a completely stock fuel system accept for larger injectors. I don't even have a shim kit in my fprv. I'd guess Im at 600 or so HP?
 

andy-stevenson

New member
Jul 7, 2013
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He doesn't mean stock injectors. I believe he's running dual stock pumps, but all his fuel lines and rails are stock.
 

hondarider552

Getting faster
May 28, 2008
10,627
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Arizona
I just took them off and took them to 1/8 diameter. ..how the heck you making 1000hp on stock fuel

I have 100% overs, stock everything else with dual pumps. :thumb:


Ive never had a shim kit, big fancy supply lines, fittings or anything for years and made good power in every one of my past duramax's
 

LBZMIKE

New member
Nov 15, 2014
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colorado
Oh ok i would think atleast duals and a lift pump but the way i see it if i cant blow through that fiiting on the driver side fuel rail how is it going to keep up when i get my efi live and the cp3 fitting was lose so i just did that one also the race valve im thinking i may not have gotten tight enough but i have a fear of breaking things so idk i cant get my tourqe wrench in there the lift pump is just for added security
 

Ne-max

I like turtles
Nov 15, 2011
3,361
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Lincoln, Ne
Oh ok i would think atleast duals and a lift pump but the way i see it if i cant blow through that fiiting on the driver side fuel rail how is it going to keep up when i get my efi live and the cp3 fitting was lose so i just did that one also the race valve im thinking i may not have gotten tight enough but i have a fear of breaking things so idk i cant get my tourqe wrench in there the lift pump is just for added security

Erase duals off your list.
 

LBZMIKE

New member
Nov 15, 2014
62
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0
colorado
I wont be putting duals on until i pop my transmission do you guys think the lift pump will cure this issue or maybe the race valve isnt tight enough ?
 
Last edited:

LWATSON

future trans limpers
Jul 30, 2008
2,587
1
36
55
Scotland Neck NC
Id fix the issue first. It could be the race plug isn't seated well enough. You shouldn't be getting a rail pressure code on a 100 hp tune.
 

Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
21,655
5,803
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Phoenix Az
You should search "fprv bottle test" and see how that works out. Then put the edge on stock and see what rail pressure does. If rail still drops a ton, put stock parts back on where you modded the fuel stuff.

Next, if you want 600hp, stop spending money on bs parts that are never gunna get you there or parts that are only temporary. Clearly you have a goal in mind

Put the exhaust on, ditch the egr, but efi live, put a lift pump on, put a trans in it, put a turbo on it and you will be getting somewhere. You need to spend some time reading on here my friend


Sent from my iPhone using Tapatalk
 

LBZMIKE

New member
Nov 15, 2014
62
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0
colorado
The only thing fuel wise i have paid for is the race valve and fuel pump i just bored out the stock fittings on my mill and my fprv was leaking but i will try the bottle test and see and egr is deleted either way the lift pump will be a good investment
 

LBZMIKE

New member
Nov 15, 2014
62
0
0
colorado
But it will work with efi live and thats why i got it i plan on getting the dsp5 and ecm tuning or maybe the hand held one to tune my self