1JZ Oil Pressure with sandwich plate

[Project-X]

I recently installed my 1JZ with oil pressure gauge from prosport I used a sandwich plate in the filter location. My 1jz is mostly stock, 3" exhaust, front mount intercooler stock boost and turbos. I looked up some some stock figures for oil pressures on these engines and people were claiming 20-25 psi idle,
45-60psi cruising, 80-100psi WOT and 80-100psi cold start.

my figures are slightly different I am getting hot idle 18psi, 40-60psi cruising, 120psi peaking WOT and 90-100psi cold start.

I was wondering if maybe my location of my oil pressure sensor has an effect on my oil pressure numbers
or is my pump tired perhaps something isn't right?

I was worried about the 120psi peak at WOT and dropping too low at idle everything else seems ok..
the oil in the car is 5w-30 synthetic any opinions are appreciated thanks.

 

[toy4speed]

Picking up the oil pressure at the sandwich plate should be fine, its pretty close to the factory 1jz oil pressure sensor location. I'm planning to use the Driftmotion adapter hose that connects to the factory oil pressure sensor port, then attach my 1/8" npt sensor from Prosport to it. Your pressure numbers look pretty good though. I would probably use a 10-40 wt oil, synthetic, but that's just me. Not sure back in the day the engines were meant to run on 5 wt (on the multi-vis). Just my thoughts, others with years of 1jz experience should chime in. Don't think oil pumps get tired, either work or not. My stock 5mge motor in my Mk2 Supra had (factory) only 5-6 psi at idle, and that was considered normal, fwiw.

Don

 

[Radial]

The idle pressure could just be a few RPM in difference at idle.... so dont worry. "High" oil pressure is not necessary a "bad" thing, could just and indication that your Bearings,Valvelifters and Oil are in good shape.

 

[supra1008]

I had bad oil pressure for the longest time. At peak wot, it wouldn't go above 20psi at idle it was fine at 18psi. I eventually realized my oil relocation/cooler lines and cooler itself were not big enough. Changed to -8 lines and cooler and now its back to normal! Luckily my bearings were fine when I pulled the motor last season and checked all the bearings and put a new oil pump in. Thinking now maybe I could've shimmed it but no big deal.

 

[destrux]

You should be running the lightest weight oil that will get you above 10psi per 1000rpm. I run 0W-30 synthetic Mobil 1 in my 1JZ. After a 20 run dyno session where I put down 370whp and oil temps in the 240 degree range, no problems. I get 100psi near 7500RPM.

Read this if you're skeptical.

http://www.bobistheoilguy.com/motor-oil-101/

The old 5W-X and 10W-X oils are outdated technology. There's no benefit to having a high viscosity warmup oil, you'll understand what I mean after you read that site. I have full oil pressure with the 0W and the car starts like it's summer time even in 20 degree weather.

If I were doing a track day I would probably run a 0W-40 though due to the high oil temps I'd be seeing (that I never see on the street, even during extended beatings).

I should also note that my car (oil temp) gets up to operating temp MUCH faster with the 0W-30 compared to the 10W-40 due to the oil flow (volume) being that much better. The oil transfers the heat away from the cylinder head into the rest of the motor much faster than before. This is good.

 

[te72]

I've run Rotella 5w-40 synthetic in my car for about 2 years now, no complaints yet. Jdub approved is good enough for me.

Interestingly though, my oil pressure never goes beyond 85psi (cold startup). 120psi seems like it would be enough to pop a filter...

 

[Dylan JZ]

yeah, in Florida heat I run Mobil-1 10w-40HM.. before that, I used 0w-30GC and found it to be too thin for my application. I might try the 5w-40 Rotella (IIRC my dad used to run that in his diesel 24' straight truck).

~80psi start-up, ~20psi idle, ~40-60 cruising, and ~80 at WOT. when it's cooler (40-60def F), the press goes up about 2-3psi but settles back once warm.

 

[Project-X]

You should be running the lightest weight oil that will get you above 10psi per 1000rpm. I run 0W-30 synthetic Mobil 1 in my 1JZ. After a 20 run dyno session where I put down 370whp and oil temps in the 240 degree range, no problems. I get 100psi near 7500RPM.

Read this if you're skeptical.

http://www.bobistheoilguy.com/motor-oil-101/

The old 5W-X and 10W-X oils are outdated technology. There's no benefit to having a high viscosity warmup oil, you'll understand what I mean after you read that site. I have full oil pressure with the 0W and the car starts like it's summer time even in 20 degree weather.

If I were doing a track day I would probably run a 0W-40 though due to the high oil temps I'd be seeing (that I never see on the street, even during extended beatings).

I should also note that my car (oil temp) gets up to operating temp MUCH faster with the 0W-30 compared to the 10W-40 due to the oil flow (volume) being that much better. The oil transfers the heat away from the cylinder head into the rest of the motor much faster than before. This is good.

good read, thanks. I will look into changing my oil a better start up would be beneficial as it is only 50-70F here right now. However this does not explain my 120psi peak oil pressure at 7000+ rpm

I haven't blown an oil filter off or anything but I also haven't heard of anyone having much more then 100 psi at WOT past 7000 RPM

 

[destrux]

Are you using the stock gauge? Maybe it's wrong?

 

[OneJArpus]

I see 70-80 psi cold, 30-40 idle (800-1k idle) (at 750 its about 25) then at full throttle it goes up to 110-120 by redline typically around the 90-100 psi area.... This is on a 1.5jz with a new pump

I have a ProSport EVO Digital Oil pressure gauge that confirmed it. I had the same readings with the stock gauge.

 

[Project-X]

@destrux , my cars a jdm jza70 no stock oil pressure gauge. i am using prosport premium series with a sandwich plate for the sensor.