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Low Oil Pressure Between Builds

crashsvg

By crashsvg,
in Engines & Forced Induction

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crashsvg Contributor

crashsvg

Posted
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Posted

its a new pump.the old and the new one wouldn't have the same problems .different housing ect ..yes the pick up inspected and clean. and oil drain bk mods at only 225hp if that much would mean this motor has serious issues if its needed .

datsun_1600 Enthusiast

datsun_1600

Posted
Posted

If you ignore blowby, HP figures are totally unrelated to oil pressure and flow. You could have a 50HP RB26DETT with oil drain back issues. Just say'n, don't rule anything out due to hp figures.

Jeff

KiwiRS4T Grand Master

KiwiRS4T

Posted
Posted

If you haven't had a good run with your engine you may not know if you are going to have oil control problems - and they are not related to hp but to revs and oil pump choice. there are two main symptoms - at extended periods at WOT such as on the straight on a track or on a dyno you can get too much oil in the cam covers so that it spews out everywhere. The other is that you can pump the oil out of your sump faster than it flows back potentially creating oil starvation. If you have the head off I would bang the appropriate restrictors in now anyway.

crashsvg Contributor

crashsvg

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yes I understand how the oil system works ..this build has zero blow by ..and as for rev ..its prob seen 5000k to redline 5x in its 400miles... when my pressure drop off its usually from a 2nd gear pull. not going tru the gears and shifting hard .. I simply accelerate from 2k and by 3k my oil is up to 60psi.by 4 stays around 65 and by 5k falls off to about 55psi and would stay there to redline if I hold it.

  • 1 month later...
crashsvg Contributor

crashsvg

Posted
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Posted (edited)

UPDATE!!!!!!

so guys i have changed the bearings and went a thou thicker ..so clearances by elimination now is about .0016-.0018 and the oil pressure is up like a bitc* ..at start up its bk to 78psi but at a blip of the throttle of around 2500k its up to 100psi n climbing ...when warm it idles at 28-30psi when heated after some pulls it rests about 22-24psi ...at 3k when hot or warm its up to 70 psi at 5k its up 84psi .... when hot after some pulls it goes around 60psi at 3k and 74-78psi at 5k and holds..i havent hit the limiter yet as i see no reason too ,, car pulls hard...

have a new problem now..lol... experiencing windage ... my rb26 is in a s15 so we used a rb25 sump ..and did a lil customising to the sump...first i had 4.5l of 20-50 oil in it and when the boost hit over 16psi the oil pressure would drop to around 35psi when it climb rpm fast ...i added 1.5l for a total of 6l and now when i boost it drops off from 82 to 70psi on pulls ...so am assuming its time to get a 7L sump to help combat the problem..

but even how its set up now am still satisfied as am only revving 6k and getting 70 plus psi will over the 10psi per 1000rpm rule...

and yes the bearings had damages to them from the break in period of just 600-800km on low to no boost ....

also my tach was off so it was more like getting 3.5bars at 4200 rpm with the wider clearance and staying there...

hope this info is help full to other builders

so rule is...... wide clearance require bigger pump or oil pressure will be on the sad side......

Edited by crashsvg

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