mine is over 9000...

 

Yours is returnless or return?

 

I know it's a vacuum canister, it's the only pic I have on my PC of my engine bay

 

Cool, I figured you were using the pic for location purposes. I wish my truck had one of those, for all those wonderful times my truck used to stall out on me

Oh and clean your engine bay

 

Return

 

how much boost do you run? 61 psi sounds too low unless you are only running 3 psi. i.e. if you are running 10 psi you're fuel pressure should be 68 psi at wot.

 

Here's the stock 317 port:
Lift......Int...........Exh
.100" ..64.8........53.3
.200"..142.1.......111.6
.300"..204.3.......146.8
.400"..233.5.......164.9
.500"..250.0.......174.2
.550"..251.2.......181.2
.600"..253.0.......184.4

PRC stage 1 317


.200"..147.......114
.300"..207.......148
.400"..255 .......187
.500"..292 .......202
.600"..313.......220


The stock 6.0 cam is something around .470 lift. If you extrapolate the above #s the ported heads are flowing something like 30 cfm more at that point. I didn't think it was that much of a difference. Today I put in a 02 0411 pcm and loaded up stock lq9 tune. It was doing like .750-.890 on the narrowband o2s, so it's pretty lean. I'm going to order the LC-1 and see what it reads. So, as the cause of my knock I ruled out so far fuel pressure, intake manifold and gaskets, PCM, oil mist, etc. I will fatten up the tune with the wideband on there and if it's still knocking at good AFR, I will add race gas and see what it does.

 

Is that the return or returnless GM spec? i guess since it is fine at WOT the pump is not causing your problems, maybe you should look into replacing that regulator... personally i would not want my FP to drop down to 49-50, wanna talk about leaning it out and toasting a motor....

 

It's return spec. The returnless trucks always run at a constant fuel pressure. It is normal for the truck to drop 3-10psi from the key on, engine off pressure. At WOT I am getting 58 psi which is great. If my motor was going to blow it would have done it a long time ago

btw, the intake, rails, injectors, fpr, etc are all brand new. The FPR is working perfectly. I pulled the vacuum to it and FP went up to 60.

 

What does that even matter, who cares about FP when the truck is not running... what you should care about is the 10psi drop when yours is running... But i agree 58 at WOT is awesome!!!