Do thinner oils (SAE xW-20, xW-30) do better at high RPMs?

Red Line High-Performance 5W-30 has about 85% API Group IV PAO and about 15% API Group V POE. You don't want to have a mostly POE engine oil unless as in the case of Valvoline/Cummins Premium Blue Restore, which is used for a single OCI for the removal of carbon deposits.


No, it is not VII-free either. Its VII content is comparable to that of lower-VII-content 5W-30 oils, such as Pennzoil Platinum 5W-30, but I've seen even-lower-VII-content 5W-30 oils.
Not quite understanding.. 15% is high POE?
POE is inferior to PAO? What about their 0W-30 grade? 5W-20? 0W-20? (10W-30?)
 
Not quite understanding.. 15% is high POE?
POE is inferior to PAO? What about their 0W-30 grade? 5W-20? 0W-20? (10W-30?)
Yes, 15% is a very high POE content. I don't know the POE content in the other viscosity grades of the Red Line High-Performance oils, but I expect them to be similar.

POE is not normally used as the primary base stock in the base oil, as it's very polar.
 
Yes, 15% is a very high POE content. I don't know the POE content in the other viscosity grades of the Red Line High-Performance oils, but I expect them to be similar.

POE is not normally used as the primary base stock in the base oil, as it's very polar.
Okay cool. Thank you for helping me understand.

I really rather like Redline oils, I understand some people don't like the (new) product?? But if there is anywhere I can look at different grades. I'm thinking I want to do as thin as possible, but thick as necessary, as it sounds like I will have a hard working engine.
 
Okay cool. Thank you for helping me understand.

I really rather like Redline oils, I understand some people don't like the (new) product?? But if there is anywhere I can look at different grades. I'm thinking I want to do as thin as possible, but thick as necessary, as it sounds like I will have a hard working engine.
I my opinion its good oil. But I'm simply not going to pay twice as much or more for oil that dose not give me double the documented engine life. Its just that simple.
 
If you are looking into expensive oils, I think Amsoil SS 10W30 is a very good oil. Noack is 4.1 One of the lowest I've seen.
 
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Higher RPMs also increase the shear rate, which increases the temporary shear (temporary lowering of the viscosity) of an oil.

For example if you have a 5W-30 and a 10W-30 with both the same HTHS = 3.0 cP @ 1,000,000 s⁻¹ shear rate but with the 5W-30 having a lot more viscosity-index improver (VII) than the 10W-30, the 5W-30 will run a lot thinner than the 10W-30 at higher RPMs where the shear rate increases beyond 1,000,000 s⁻¹ at which the HTHS is measured.
That's a good reason to compare the VI when look for oils for a high revving engine, and don't go for ones with a huge viscosity index.
 
....
My question then is how can going from 2.5 L to 2 L NOT yield higher RPM?
....
How can going to a different engine size yield a higher RPM?

Engine size has ABSOLUTELY NOTHING to do with RPM at a given speed. And Neither does the flywheel.
That's all gearing and tire circumference .

EJ engines hate pennzoil. I would run the Subaru Idemitsu 5W30 or M1 5w40 or Valvoline advanced 5W30 or EDGE 5W30

Is the 2 litre JDM engine a DOHC with AVCS (VVT) ? If so stick to OE viscosity recommendation.
My EJ253 is AVLS so they don't care about viscosity and want a near 40 grade to be happy.

I've owned 9 Subarus over decades. And BlueSubie on here is a Subaru Guru with turbo experience.

I was never that brave. Like strapping dynamite to a box of grenades :)
 
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I am curious myself. This is somewhat of an experiment, I will agree. Combine that with our fast roads the U.S. if RPM stays the same but load on the engine is increased. Sounds like a case for the best synthetic oil around, I'm thinking a thin 30, since 4k has been called "not high RPM" and someone mentioned the occasional fun blast won't hurt it..

I'm thinking a synthetic 0W-30, after the oil starts darkening. I hear these JDM engines sit around without oil in them?
Read my previous post.
Going to that little 2 liter is not going to be "fun" or "good"

I Just hope it gets you from A to B.
And the ECU definitely need a different baseline program. - absolutely NO doubt about that

I don't see the fascination with "JDM" Unless its a car like the Skyline we don't get here.
Your old EJ253 was Made in Japan.

I'm trying to remember. is this motor going in a Old outback with a 4EAT?

If so, Cancel the order on the JDM 2L. NOW!
That motor would only be good in an old mid Nineties Impreza with a stick.

That's my WELL CONSIDERED advice, since you don't have anyone really HELPING you here, just a bunch of
time -wasting Jibber Jabber.

- Old Uncle Ken

Subaru Gunma, JP Factory
937bb1552063713N Subaru plant.jpg
 
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Car gearboxes use fluids that are on the thin side. 75w, 75w80, ATF etc. Most manual gearboxes run fluids that are similar to a Xw20 or Xw30 and even thinner if you compare data sheets.
When it is separate sump, it is easier to design specific oil for that purpose. When it is #hared sump, there is quite a challenge to provide shear stable oil and not causing LSPI with reduced SAPS formula.
 

Not sure about him claiming that the oil in the pump just keeps going "round-and-round" in the pump if it's in pressure relief. Typically, PD oil pumps will direct excess oil back to the sump when the pressure relief valve opens, but maybe Subaru oil pumps are different - ??
 
Not sure about him claiming that the oil in the pump just keeps going "round-and-round" in the pump if it's in pressure relief. Typically, PD oil pumps will direct excess oil back to the sump when the pressure relief valve opens, but maybe Subaru oil pumps are different - ??
From what I saw on the video, it seems it gets pumped into one of the heads and not the other one and that would make it interesting indeed!
 
The EJ20 was sold in vehicles here, why not look at a 2004 impreza or something that would have come with the EJ20 and see what it was recommended
 
Not that it matters, but I have confirmed 2x with Dave at Red Line that their HP oils use in the range of 40% POE.
 
That's why I was anticipating higher revving, engine has to do more work.

The H6 had either 212 or 232HP.

Will I see better gas mileage?

If the engine can manage the same speed in the same gear then yes. If the transmission decides to shift down because you push the acellerator further, then no it will likely be worse.
 
I really want to bug a 2008 Subaru but for now.. I got this one.
 
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