What is normal oil pressure?

[JmP6889928]

I have both gauges in mine. I have the electric AEM gauge on the dash and I have the mechanical "truth" gauge under the hood.

 

I have had electric gauges fail on race cars before and pull in to find nothing wrong, so years ago, we put mechanical gauges under the hood for oil pressure, fuel pressure, oil temperature, coolant temperature, and cylinder temperature. This way, if there is a bad read on the dash, come in, open the hood quick, slam it back down, and either save the engine or all is good and back out.

[Knapp]

Is there a thread on how to install an oil pressure gauge? I'd like to keep an eye on mine being that the car is getting older

[Volta55]

Is there a thread on how to install an oil pressure gauge? I'd like to keep an eye on mine being that the car is getting older

 

I wish I can help ya.. because I am in the same boat

 

http://legacygt.com/forums/showthread.php/oil-pressure-gauge-install-empty-oil-galley-24956.html

 

 

broken pic links

[kzr750r1]

It's a simple install but be wary of hose extensions. I had a mechanical glycerin filled gauge extended from the rear galley. Failure could have been exasperated due to the fact I didn't fix mount the gauge. But the hose did begin leaking at the block side. This was mostly just meant for assurance I had oil pressure at startup after my rebuild. Recently removed the adapter and plugged the rear galley again till I can source all the right bits to install a pillar gauge.

[StkmltS]

My electronic sensor (monitored via awesome BtSsm) is in the rear galley.

 

If you're less adventurous than deleting the TGVs you could add a "Y" to the front galley and add a pressure gauge/sensor right next to the OEM one. If that spot was good enough for Subaru engineers then it should be good enough for us.

 

The absolute easiest option is to add a sandwich adapter to the oil filter.

[Volta55]

My electronic sensor (monitored via awesome BtSsm) is in the rear galley.

 

If you're less adventurous than deleting the TGVs you could add a "Y" to the front galley and add a pressure gauge/sensor right next to the OEM one. If that spot was good enough for Subaru engineers then it should be good enough for us.

 

The absolute easiest option is to add a sandwich adapter to the oil filter.

 

Thanks alot.. I might do the front galley. it seems that all you do is remove the alternator, and install the T or Y fitting.

 

now.. to get temp/pressure to display on my BTSSM.

In the BTSSM thread, people do include the manual inputs to display oil temp and pressure, but i am confused and curious as to what is "in-between" the sending unit and BTSSM... do you wire it to the ECU?...most likely not.

[StkmltS]

Thanks alot.. I might do the front galley. it seems that all you do is remove the alternator, and install the T or Y fitting.

 

now.. to get temp/pressure to display on my BTSSM.

In the BTSSM thread, people do include the manual inputs to display oil temp and pressure, but i am confused and curious as to what is "in-between" the sending unit and BTSSM... do you wire it to the ECU?...most likely not.

 

You're welcome. This stuff gets confusing so I'm glad to share what I've learned when I can.

The signal from the new sensor does go to the ECU, but it goes through the deleted TGV sensor. So yes, but no

Your ECU will think it's seeing good (but funky) data from the TGV sensor, which is why you have to disable the CEL associated with deleted TGVs.

 

Within BTSSM you just add a custom field with the TGV sensor address and the correct formula to change the value into what you want.

If you get that far and need more info there's a thread somewhere about monitoring wbo2 via deleted TGVs, or you can post back in here, the BTSSM thread, or shoot me a PM.

 

The electronic sensor (pressure transducer) has three wires.

1) positive 12v input (connect this to a power source that's only on when the car is on)

2) ground (connect almost anywhere)

3) 5v "signal" out (directly goes into the unused female TGV sensor harness)

 

** this only works as easily as it does because the pressure sensor output (0-5v) happens to be exactly what the ECU is expecting to see from the TGV sensor (0-5v) **

 

How mine is wired:

All three wires from the sensor are plugged into the female TGV sensor harness.

I used this transducer but there may be cheaper options (for the same thing) depending on when/where you buy.

 

The exact same setup can also be used to monitor fuel pressure.

 

A wideband O2 controller (what creates useable data from a wbo2 sensor) also outputs 0-5v, so it plugs into the TGV sensor harness in the same way... but a WBO2 controller uses way more power (insert correct electrical terms here) so the 12v and ground need to come from somewhere else, NOT the TGV harness.

[elver231]

Hello. In my case, I own a 95 Subaru Legacy. I recently made all engine, a very detailed job. Recently I put an AEM oil pressure meter and values are as follows: idle, cold: 88 - 92 psi. Cruiser @ 3000 RPM: 70 - 76 PSI. idle, hot: 33 - 35 PSI. Full gas: 85 - 90 PSI.

I wanted to share my values, I was thinking it could be interesting for some of you to know how was oil pressure behaviour in older cars.

 

Greetings from Ecuador!

 

Enviado desde mi HUAWEI NXT-L09 mediante Tapatalk

[Tronic]

Probably wouldn't run a 5W oil, try a 10W oil and your hot idle oil pressure will come up.

 

I would have thought that 10psi is pretty low but it depends on where your reading it.

 

No gauge on my Subaru's but for my Toyota its 17psi for 5W and 22psi for 10W at the oil filter for hot idle. I added a sandwich plate thats full of 1/8" npt bungs that you can simply screw a pressure sender into one of them.

 

I suspect if you start putting your sender into the oil galley in the head for example your going to get a lower reading. I prefer adding a plate and this way you can keep the stock oil pressure dash light in the head.

[rhino6303]

Blah.

[JmP6889928]

The engine compartment looks great. Uhhh......the stretch on the wheels accomplishes........what?

[fullerslgt]

Ok I’ll give that a shot on next oil change. I was told the bardahl b2 oil helps also, you know anything about that stuff?

[ehsnils]

Probably wouldn't run a 5W oil, try a 10W oil and your hot idle oil pressure will come up.

Look at the figure to the right of the "W" for the hot viscosity, that's the one that really matters at that time.

 

 

If you see a difference of the viscosity when hot when you change the figure to the left of the "W" then you are ripped off by someone re-labeling cheaper oil.

[Tronic]

Look at the figure to the right of the "W" for the hot viscosity, that's the one that really matters at that time.

 

 

If you see a difference of the viscosity when hot when you change the figure to the left of the "W" then you are ripped off by someone re-labeling cheaper oil.

 

I disagree, I have only ever used premium brands like Castrol and Mobil.

 

If you have an oil pressure gauge you will notice a drop in your hot oil pressure at idle.

 

0W I had 12psi, 5W I had 17psi and 10W is 22psi.

 

Big differences. the W is not telling the whole story because the oils were 0W-30, 5W-50 and 10W-60 so nowhere near directly comparable. The 0W oil didn't last long in the car, changed it after only 2000km as the low and erratic pressure was a bit unnerving. Of course if you don't have a gauge you would never know you had a change in pressure, all oils still above the oil pressure light coming on.

[rhino6303]

I disagree, I have only ever used premium brands like Castrol and Mobil.

 

If you have an oil pressure gauge you will notice a drop in your hot oil pressure at idle.

 

0W I had 12psi, 5W I had 17psi and 10W is 22psi.

 

Big differences. the W is not telling the whole story because the oils were 0W-30, 5W-50 and 10W-60 so nowhere near directly comparable. The 0W oil didn't last long in the car, changed it after only 2000km as the low and erratic pressure was a bit unnerving. Of course if you don't have a gauge you would never know you had a change in pressure, all oils still above the oil pressure light coming on.

Science disagrees with you though. The W stands for "Winter" and hence is for colder temperatures. If you are seeing pressure differences it is most likely placebo and the actual psi difference is pretty negligible.

 

Do us all a favor and perform the following back to back to back to back test.

 

Change oil with 5W-30. Warm it up. Drive a few miles. Video record the oil pressure when cold and warm.

 

Immediately change the oil with the same brand but use 10W-30 and repeat.

 

Immediately change the oil with 5W-40 and repeat.

 

Immediately change the oil with the same brand as 5W-40 but use 10W-40 and repeat.

[Tronic]

Quite funny.

 

I have already done the testing, why don't you do it and report back.

[rhino6303]

[emoji38] Quite funny.

 

I have already done the testing, why don't you do it and report back.

Because I trust science and haven't ever noticed a real difference between 5w-40 and 10w-40 when the engine is up to operating temperature. It's probably because they were designed to be the same.

[StkmltS]