RB25 Oil Pressure

[BenOswald]

What kind of oil pressure do you RB guys get, when hot. What oiling set ups are you using, (stock pump, oil cooler, restrictors etc). How much PSI at idle and under load is considered healthy?

Im thinking my oil pump is very worn.

Thanks.

[steveo1502]

Do u use an aftermarket gauge, those stock ones can be way off

[mightyrocker]

Your oil pump could be worn..... but more likely you're getting too paranoid because the stock gauges are bitches (yes so is the oil light).. My oil light comes on at 50 psi but not at 20, and then back on at 15. lol


You should be seeing (very ish) 15 psi at idle; 50 while under load at cruising speed and anywhere from 70-95 around redline

It really depends on your oil but you should be somewhere around there. I run whatever 10W 30 synthetic that is on sale. Every oil gives me slightly different readings @ OT. I have seen as low as 12 psi at idle on a hot day on multiple RBs with no issues.

[steveo1502]

Yeah, mine too, although I've never seen the light come on but goes real low at idle,

[BenOswald]

I am using an aftermarket gauge and 20w-50 oil.

Thinking about buying either an N1 oil pump or a standard rb25 oil pump..

[steveo1502]

20w50 is way too thick, could be why the low pressure, why do h run such thick oil?

[mightyrocker]

haha holy ****. if you aren't getting oil pressure with 20w50 i don't know what will

unless you have a 12L diesel skyline might I suggest a different oil?

[BenOswald]

I run that weight because, thats what the motor is clearanced for, to maintain reliability under heavy use. the heavier oil would also increase oil pressure, Im gonna try a oil additive to at least bump it up a bit. I might try to shim the pressure release valve but thats the same amount of work as replaceing the pump..

[steveo1502]

20w50 is way too thick, could be why the low pressure, why do h run such thick oil?

[h4X6]

what is recommended for skylines then... i think that what i was using was 20w50.... 10w30 is to thin...

[steveo1502]

Really? I'm not even sure, thought it was 10 w 30, that's what I use, I don't think any cars recommend 20 w 50, I only use that if the rings are shot and smokes blue, lol. Guess it wouldn't make that much difference now it's summer but would be thick in the cold

[mightyrocker]

If you have oil pressure problems the 20w50 is probably why.

That's thick enough that you could start causing problems too (hydro lifters etc..)

Nissan recommends sae viscosity 30 oils(0w30-5w30-10w30).... they are NOT too thin.... we all have good oil pressure with these oils.. cant argue that. If you are running different bearing clearances.... or If you are running unusually high oil temps (racecar-45 degrees out) then you need a 40 or 50 to get the same cst as we would in a stock motor in calgary.

but yeah


Stop listening to 65yr old ford mechanics

[xcye]

Is your motor rebuilt? When you say "thats what the motor is clearanced for", do you mean the bearing clearance is set very large when it was rebuilt. If so, you need to buy an aftermarket oil pump which can pump a lot more oil than standard ones( and N1s) can.

I run that weight because, thats what the motor is clearanced for, to maintain reliability under heavy use. the heavier oil would also increase oil pressure, Im gonna try a oil additive to at least bump it up a bit. I might try to shim the pressure release valve but thats the same amount of work as replaceing the pump..

[BenOswald]

The clearances are larger than stock so the motor doesnt wear its self to bits within a year. There are quite alot of modifactions done to my set up, it only puts down stockish numbers due to the size of the turbo currently on it. GT2535r. I'm going to trust my engine rebuilder of most people concerning what i should use for oil. Anyways.. i found a N1 oil pump in town i will be picking up before the weekend, then ill pull the motor and swap pumps and have her sealed up by sunday again if all goes well.

"Build em loose, they'll handle Boost.."

Thanks

[mightyrocker]

ahhhhhh built motor!

well that makes sense