Rb20det oil pressure concern

[will.geez]

Hey all,

Recently put a new forged rb20det in my 32 gtst. According to my aem gauge my oil pressure is 16psi hot idle, 57psi hot redline (7k rpm). 70psi cold idle and goes up to 100  psi cold revving. I’m using penrite 10w50 full synthetic oil. I’m happy with the idle pressures however hot redline pressure seems low at 7000rpm since it’s 57psi. The factory service manual states 56 psi at 6000rpm however since mine revs to 7000rpm I feel like it should climb more but it doesn’t. I’ve spent too much money on this already and would hate to stuff it up due to oil pressure. Oil Pump is a factory pump. Can anyone ease my mind or give me advice if it’s safe to beat on with my described pressures. Done research on Facebook and everyone’s oil pressures are all different. Some people are saying it’s ok, some are saying it’s too low since they get 70-80psi at redline. Really confused and want this solved. Keep in mind no head drain or restrictors either. Cheers!

[Duncan]

You need to ask your engine builder this question, not the internet, because the internet won't be the people you argue with if it fails.

You should also consider that you gauge may be inaccurate, you are best to hook up a mechanical gauge to check it.

But yes, it looks low to me at idle and a little low at full revs, even for a factory pump. Most builds would use a higher flowing pump with a 100psi relief spring so they tend to run around 100psi at full noise.

[Ben C34]

How does the oil look?

I would be concerned with that pressure assuming gauge is correct

[BK]

Standard oil pressures for RBs from 33 manual:

Definitely appears low and doesn't install confidence, but stock oil pump hot pressures of about 15 psi on an RB0/25 or above 22psi on a 26 are normal at idle.

If you had a non standard oil pump its definitely a concern - our white 32 RB26 with tight bearing clearances has 15psi hot idle pressure with a Nitto pump. (not good)

As mentioned you really need to ask the engine builder on what bearing clearances were set as large clearances reduce oil pressure. If clearances are larger like used for bigger power applications, larger pressure / volume oil pumps are fitted to compensate for this.

Tread with caution as your higher rpm oil pressures are more concerning.