Using turbo oil pump on nonturbo

[entirelyturbo]

... is there any benefit?

I'll likely be resealing my engine soon, and with the reasonable cost of a brand-new oil pump from Subaru, I was just gonna replace mine with a new one. A turbo one is the same price as a nonturbo.

So, would there be any good reason to do so?

[Arctic Assassian]

Besides making more pressure, not really.

[GeneralDisorder]

I doubt it would hurt anything, but the turbo's use added pressure both to compensate for the oil-squirters and the turbo - every hole you punch in the pressurized gallery means less pressure to each component so you increase the gallery pressure and volume to compensate. Also the additional load on the rod journals when under boost means it's easier to overcome the oil film layer that protects the metal - higher oil pressure forces the oil film into the gap - like inflating an air mattress more if you are heavier.

GD

[entirelyturbo]

I'm sure it wouldn't hurt anything, but I'm not sure it would be of any benefit either.

More oil pressure obviously sounds good, but...

1) would it offer my nonturbo engine any benefit? Easier on valvetrain/bearings/etc.?
2) wouldn't the relief valve just open more to compensate for it, not giving me any extra pressure to begin with?

[GeneralDisorder]

I beleive the releif valve is in the pump so it's going to put the gallery at whatever the turbo oil pressure spec is. I don't have it handy....

But the EJ22E is known to last 300k without major mechanical failures on the stock pump.... if you were planning on adding like 5 psi of turbo to it then I would say go for it - otherwise I don't think there's much benefit to be had. If the stock pump isn't enough then there are serious internal problems that aren't going to be fixed by increaseing the pressure.

The reality is that the 22E doesn't have a demand for the volume and pressure of the turbo pump or Subaru would have put it on there in the first place. As you see the price is not the issue. I would err on the side of caution and assume the Subaru engineers knew what they were doing when they spec'd the pump. You never know - maybe it will hurt the NA lifter or something. I don't know enough to say.

GD

[entirelyturbo]

I figured as much.

What I was going to do was rebuild my original one. New rotors, relief valve, full reseal, what not. But just the cost of those parts is very close to just replacing the whole damn pump. So I was considering just replacing the pump, and as the adage goes, 'if you replace, upgrade.'

But no point if there's no benefit. So I'll just stick with what I have.

Thanks for the help.

[Imprezive]

N/A oil pump maximum pressure: 71psi
Turbo maximum pressure: 85psi

If you wanted, you could shim the relief valve spring to add some pre-load, thus stiffening the spring and bumping the max pressure of your N/A pump up. By how much I have no idea.

Either way I doubt it would make a difference, if you are just running around with a stock engine there is no need for more oil pressure. I would check to make sure your original oil pump is still able to put out around 70psi, and when you pull the engine apart, measure all the tolerances in the pump to make sure they are also within spec. If you've be reasonably good to your oil pump and it hasn't swallowed any metal, then it is probably fine.

[93forestpearl]

A higher volume pump really isn't necessary on the 22E. I used to beat mine like it owed me money, and no issues when I pulled it at 200k.

[Legacy777]

Too high of a pressure can be a bad thing too. Not sure if 14 psi is going to make a big difference, but too much oil pressure may cause issue with seals.

[SiCkSTi04]

im thinking of replacing my 91 stock na oil pump with an 02 wrx 10mm pump. this would be a bad thing? 42k miles compared to my 165k pump.

[Matt Monson]

I run a 10mm WRX pump on my hot rod 2.5RS engine. It's only been on there 5000 mi or so, but I haven't seen any problems. I wouldn't expect there to be a problems with things like seals since the Ej22E and Ej22T both use the same cams seals, oil pump seals, main seal, etc. It's not like the NA cars have lower quality seals on them. They're the same parts.

[tahiti350]

It would probably have a small, possibly noticable affect on fuel milage due to using more power to turn the higher pressure, adn if it bypasses it out of the pump would heat the oil more.

Sounds like a waste to me..

[SiCkSTi04]

would any know the oil pressure/MM off the 1996 2.5 impreza's and 1995-1996 impreza 2.2