Still low oil pressure
When I built my motor over the summer last year I replaced the oil pump with a ported ls6 one. I still have the stock shortblock but I changed the rest. Once I had everything back together my oil pressure was about what it is now except my #8 lifters started ticking. I did some research and determined the o-ring was pinched. Two days ago I pulled apart the front of the motor and replaced the o-ring. The old one didn't look pinched but it did look a lot smaller than the new one I got. I made 100% sure I did not pinch or cut the new o-ring so I am confident it is not that. After putting new oil and a filter in (Mobile 1 5w30 full synthetic and Mobile 1 filter) I started it up and it held pressure on cold idle of around 50 or so then lowered down to 40psi when it was warm, where I expected it to be. After letting it idle and circulate for a bit I gave it a few revs to see if the pressure would increase, and it did. The lifter tick was gone and so I thought I fixed the issue.
However, on my drive home, the pressure when right back to what it was doing before I replaced the o-ring. I did not hear the lifters ticking anymore so that was a relief to me but my oil pressure is still low. What else could it be that would cause the oil pressure to stay low like that? To my knowledge of what I have seen, I am not leaking oil anywhere so I am at a loss of what it could be right now. Thankfully I still have pressure, but I am just not sure if it is enough.
this is what i've seen and what i like to see
15-25psi idle -low but ok
25-35psi idle- normal
40-50psi idle- above normal and good
45-50psi WOT - low but ok
50-65psi WOT - normal
65-80psi WOT above normal and good
its all about how the oil pressure rises with RPM. rule of thumb is 10psi per 1000 rpms
this is what i've seen and what i like to see
15-25psi idle -low but ok
25-35psi idle- normal
40-50psi idle- above normal and good
45-50psi WOT - low but ok
50-65psi WOT - normal
65-80psi WOT above normal and good
its all about how the oil pressure rises with RPM. rule of thumb is 10psi per 1000 rpms
The bare minimum is supposed to be 10 PSI per 1K RPM for most motors. Nissan motors scare the hell out of me, I have a frontier that hot idles at 12 PSI and is completely normal, most master techs say that 7-12 PSI hot is normal.
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I would also recommend that your replace your LS6 oil pump with a Melling 10355 oil pump, and install one of Melling's orange - M35507 - pressure relief springs. See the chart below for the flow characteristics of the GM pumps versus the Melling pumps:

Good luck with your decision.
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