i've built up rb30 with internal work and turbo etc.. i put in a rb25 oil pump with a built up crank to suit but i'm getting oil pressure at about 130+ psi while driving with acceleration, i've dropped my sump and put in a rb30e oil spring but still getting high oil pressure, i used the rb25 inner spring and a na spring witch was 2 coils shorter then the rb25.. would there be any one else who has had this problem.. Some original photos have not been recovered yet.

You are in danger of blowing the rolled edge of the oil filter apart man....

Wow that's crazy. You sure the gauge is OK? I put RB25DET pump in mine without modifying the spring and it makes about 75psi pressure at 5500rpm with GTX3 15-40 oil. I vaguely remember reading somewhere about pushing the crank seal in too far and blocking the little gallery that's in there that I think exits at the bottom of the pump. I think that has something to do with bypass of oil but it's only a very small hole the whole way through.

i've listed the specs before, rb25 pump on rb25 engine is below 80psi @ 6000rpm 50psi @ 2000rpm 14psi @ idle rpm but if you have the rb30 block with no oil squirters etc, you should get close to the relief spring pressure at lower rpm. i would be checking the guage with another and also, making sure the oil is correct viscosity and operating temp before doing the pressure check.

hmm on at 1000rpm it sits at 30psi and gradually goes up to 100psi at about 4000rpm past that it keeps going and hits the needle on the end of the gauge lol will get another gauge..

What weight oil are you using???? 20/70?.................. Should be a 10w/40 on a fresh motor or 20w/50 no thicker....

20w/50..

I run the RB25det oil pump on the rb30det recently clocked over 90,000km's. Cold it peaks at 100psi. Any where from 2000-3000rpm. Once warm over 4500rpm it peaks at ~90psi.

The R32 GTR pump we put into an engine was making 120psi at full noise. They are a very similar pump the to RB25 one aren't they? Put the RB30ET one back in and the oil pressure has been normal ever since.

The standard GTR pumps are the same as the 25t pump. It wasn't an N1 pump you fitted up?

Not as far as I know. Is there any unique markings or numbers on the N1 pump?

I've got some pics at home I'll check after work. The N1 pump looks the same from the front. Backing plate has more screws. N1 Gears are thinner and hardened = more brittle = don't like small crank snout drive and hitting the limiter.