Jump to content
SAU Community

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

wsln33

By wsln33,
in Engines & Forced Induction

 Share

Recommended Posts

wsln33 Collaborator

wsln33

Posted
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

Posted
  • Author
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?

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

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • RP1421
      S15 Spec R

      By RP1421 · Posted

      A few small updates since the previous post and lessons. I decided to do a little interior light upgrade on the 110. I quite like the iilumo items, even if they're a bit of a premium over other brands. You'll also note the Stedi Fogs, that will go into the S15 fog lights as I needed to match the bulbs since I got the new ones earlier. I hope they fit as the body is quite a bit longer than your normal bulb.  Annoyingly, I managed to trip the fuse, which normally wouldn't be an issue until I located the fuse. I can't say I've ever come across this. I had lucked out that someone nearby had a spare, but oddly enough Toyota dealerships seem to keep this in stock. I ordered some to keep in my stash and as luck would have it, someone else nearby tripped the same fuse so I passed on the favour.  I also did a little service on the 110 ahead of some additional work coming up. It's been annoying that Goleby's stopped carrying this particular HKS filter for the 110, so now I need to keep them on order from Japan. I also took the opportunity to install a bash plate and number plate riser. The plate riser is such a cheap but nice fix to help really tidy up the car. I'm tempted to now also replace my headlights, on this car. Both items were from Project Aero.    I also needed to replace the rear tyres on the 110, and after trying to get it aligned learnt that I need to replace some bushes in the front end, so that's next.  Closing out this update with a nicer picture as always! 
    • Murray_Calavera
      WTAC 2025

      By Murray_Calavera · Posted

      Yeah mate, never miss it.
    • Ozdavroz
      WTAC 2025

      By Ozdavroz · Posted

      Any going to watch World Time Attack at SMSP this year?
    • Jarsky
      R33 Fuel Pump & Brakes after alarm swap

      By Jarsky · Posted

      Appreciate the correction on the "ground", that will make a huge difference to looking at this. That makes complete sense about AF70/AF71 which is what I had come down to being the issue, one of these. I'll have another look in the ignition wiring when I get a chance next week. I'll also make up a jumper wire for running that AF73 test.  ECU is fine, relay itself is fine, pump harness is fine and the pump itself is fine. I am going to upgrade the Walbro 255 anyway with a DW300 I have since I need to replace the fuel sender and I'm going to upgrade the FPR with my chasebays kit ready for new plenum/injectors/dbw, but I'll get this working first. That's why this is so frustrating. 
    • zillah
      Recommendation for engine oil funnel spill free

      By zillah · Posted

      hahaha good on
×
×
  • Create New...