Forged Rb25 Lifter/possible Oil System Problems.

[DanielH]

Yes i got the right springs for 9mm lift, that I'm sure of, and that's some good info regarding oils there, I haven't touched this for a while now, gave it a good run around the track without any dramas and it's been parked up since what is this 10psi/1000rpm guide you speak of?

[MrStabby]

10psi/1000 is quoted a lot, but i don't know where it came from so i just checked the RB26 manual, it says;

Idle: 21psi

2000rpm: 43psi

6000rpm: 65psi

all for oil at 80 degrees C

Might well be different for the RB25 tho given lifters, VCT etc.

[89CAL]

10psi/1000rpm is just a rough number to use as a guide. Of course its not a definative figure, I usually see around double that until I hit the relief which I think is just a touch over 100psi

[DanielH]

Yeah mines higher than that by a little, approx 30psi at idle, 65-70psi on the relief valve by about 3000rpm, holds that fairly consistently to redline.

[AngryRB]

After replacing lifters in my LS1, I doubt the oil viscosity and pressures is all that significant, I pulled out a few that were solid but many that had bled out badly and the motor isn't dirty,

I think just call it how it is, the lifters are near 20years old, they have done their job, time to replace..

[89CAL]

Yeah mines higher than that by a little, approx 30psi at idle, 65-70psi on the relief valve by about 3000rpm, holds that fairly consistently to redline.

Unrelated to your lifter issue, but if it were me id think about doing something with the relief valve on the oil pump. That seems awful low for relief pressure. My tuner even suggested mine could go up a touch but its not an issue that warrants adjusting it at this stage

Id agree that you might benefit from new lifters. Even second hand lifters out of a lowish km car

[zebra]

100psi hot oil pressure is stupid