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Hhigh Oil Pressure With Jun Pump Then Drops At High Revs?

wsln33

By wsln33,
in Engines & Forced Induction

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wsln33 Collaborator

wsln33

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Posted

Hey guys,

I just got my car back from a 3 year build. Its a 26/30. It has a jun pump.

All is going well with it but the tuner says the oil pressure is high at around 130-140 psi but then drops to 120ish over 6500rpm. He was concerned about this? Do jun pumps usually run this high? and is the dropping oil pressure a concern or is it still plenty of oil pressure to keep everything happy?

The Dan Grand Master

The Dan

Posted
Posted

You'll have problems with that much oil pressure.

110 is probably the maximum you would want to see. 90-100 is more normal.

What bearing clearances were used and was the pressure relief valve checked before the pump went on?

wsln33 Collaborator

wsln33

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You'll have problems with that much oil pressure.

110 is probably the maximum you would want to see. 90-100 is more normal.

What bearing clearances were used and was the pressure relief valve checked before the pump went on?

Dont know the bearing clearances right now. I wouldnt think the pressure relief valve was checked. The pump was just put on. How should the relief valve be checked?

What sort of problems will I have with that much oil pressure? Im running the engine in at the moment and have to put 1000km on it so will it be ok before I have to take it back?

Thanks mate

Swiper the Fox Grand Master

Swiper the Fox

Posted
Posted (edited)
dont the 30 pumps run the small oil pump drive though? im talking on the oil pump not the crank.

thats correct...the pump is a different gear design and is not prone to the Jap pump problems. Pull one apart and you will see what i mean.

crack off pressure is the point at which the relief valve opens.

Edited by DiRTgarage
shanef Grand Master

shanef

Posted
Posted
thats correct...the pump is a different gear design and is not prone to the Jap pump problems. Pull one apart and you will see what i mean.

crack off pressure is the point at which the relief valve opens.

thats right they are like the tomei pumps, they run a 'spline' drive gear setup

i wouldnt trust one on a big dollar motor though

Swiper the Fox Grand Master

Swiper the Fox

Posted
Posted (edited)
thats right they are like the tomei pumps, they run a 'spline' drive gear setup

i wouldnt trust one on a big dollar motor though

But your not Maatouk's, Birrong Automotive, JW Auto etc running 8's with them

Dan what problems will around 135psi at low RPM produce?

Edited by DiRTgarage
Swiper the Fox Grand Master

Swiper the Fox

Posted
Posted (edited)
Thats probably why you only run 9's. If you ran the 30 pump like all those other fancy stables you might crack 8's. :cool:

lol...im struggling to even run a 9 now, we will see what happens when the car arrives up here to race. A few little tricks we have planned for it.

Also you can add JPC and most of the Melbourne VL boys to that list.

Im currently running a JUN pump now but will go to a Peterson external pump when it breaks.

My forklift bottom end will run a VL series II or VL turbo pump (they are the same) reco'd and modified by JW Auto.

Edited by DiRTgarage
FineLine Grand Master

FineLine

Posted
Posted
lol...im struggling to even run a 9 now, we will see what happens when the car arrives up here to race. A few little tricks we have planned for it.

Also you can add JPC and most of the Melbourne VL boys to that list.

Im currently running a JUN pump now but will go to a Peterson external pump when it breaks.

My forklift bottom end will run a VL series II or VL turbo pump (they are the same) reco'd and modified by JW Auto.

A little birdie told me the car is only 2 minutes from my pad as I type.

Might go round and key it tomorrow. :blink::cool:

Swiper the Fox Grand Master

Swiper the Fox

Posted
Posted (edited)
A little birdie told me the car is only 2 minutes from my pad as I type.

Might go round and key it tomorrow. :blink::cool:

your 'little birdy' has been snorting too much powdered cuttlefish.

i know where the car is and its no-where near you Fox.

Edited by DiRTgarage

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