Another Subaru thread?

lul is that all you wanted to say? Where is all this factual information you are getting this from? Come back when you can explain why Subaru suddenly decided to change to a 20wt in a hotter performing engine outside of quoting cafe standards.
It's simple. The engineering, add packs, and chemical makeups of 20wt oils are stronger than you're willing to believe. You also seem to forget there are multitudes of ways to control and remove heat from an engine.... Pro Stock engines run 0W5 oil, and turn 10k+ rpm and make nearly 7 times the power of the Subaru. Here's some science for you:

Driven Racing Oils said:
Next generation mPAO synthetic base oils deliver a viscosity index approaching 200, and that is a game changer. Using an mPAO based oil, you can now safely run 1 viscosity grade lower that you would using a conventional based mineral oil. If you are running a conventional 20W-50, just by changing to an mPAO based 10W-40, you can reduce start-up wear without sacrificing high temperature durability or oil pressure. Driven Racing Oils
Hence, with upgrades to 20wts thru things like dexos1 Gen 2 requirements, along with other strict tests for durability, it's certainly possible to run a thinner oil, especially when you've got engine dynos and testing methods to verify results.
 
It's simple. The engineering, add packs, and chemical makeups of 20wt oils are stronger than you're willing to believe. You also seem to forget there are multitudes of ways to control and remove heat from an engine.... Pro Stock engines run 0W5 oil, and turn 10k+ rpm and make nearly 7 times the power of the Subaru. Here's some science for you:


Hence, with upgrades to 20wts thru things like dexos1 Gen 2 requirements, along with other strict tests for durability, it's certainly possible to run a thinner oil, especially when you've got engine dynos and testing methods to verify results.

What you provided is a moot point. Those engines are specifically designed and the tolerances in those engines are light years different from a consumer grade engine. They also get torn down **** near every pass. Apples to oranges bud. Nice try though.
 
Don't bother with the UOA. At all. Voluminous data on new engines shows high shear rate and so much wear-in material NOTHING can be determined inferred or baselined. If you try, you are just fooling yourself. Save the money for the good oil (and filter). Buy the end of the third fill you can start data collecting if that's your game.

The large bore Suburu will usually tell you what they want for oil. They are NOT supposed to be noisy. None of my eight were ever rackety when feed a proper diet and in good repair. If you drive it and after a spirited run t seems noisy and "out of enthusiasm" the you need more HTHS. It's not an all or nothing game. Mobil1 0w40FS makes a good top off for viscosity and AW/ EP boost. At some point the motor will start loosing rev-ability and throttle response. This is your upper viscosity threshold.
The RL is a nice choice but as other have stated, one may worry about the high mineral salts in that robust oil. They may deposit at high temps where you DONT want them and your engine will loose tune.

Now, if this 2.4 motor runs fine on a full sump of ~3.2 HTHS 30 grade. There you go. Nothing to worry about.
I would want to log fuel economy and oil temps to insure the engine is within its happy spot.

Enjoy. Now I am curious to look at this engine. The FB20 was a robust but weak engine with extremely poor tuning with the manual transmission on the Impreza. I've just driven four samples over 2 week all new - except one.

They are all abysmal.

. I am looking for an improvement from subaru here. They are a great buy with the std ADW. Roominess and Quietness is improved - Handing and helm response needs sharpening - just to be on par with anything else. The cars of the mid 90's were more enjoyable by a LARGE margin. I've owned eight and I trying for a ninth this month. I don't want to end up with a FWD Forte if I don't have to.

- Ken
FB20? Confidential BRZ excellent FA20, right?
 
It's simple. The engineering, add packs, and chemical makeups of 20wt oils are stronger than you're willing to believe. You also seem to forget there are multitudes of ways to control and remove heat from an engine.... Pro Stock engines run 0W5 oil, and turn 10k+ rpm and make nearly 7 times the power of the Subaru. Here's some science for you:


Hence, with upgrades to 20wts thru things like dexos1 Gen 2 requirements, along with other strict tests for durability, it's certainly possible to run a thinner oil, especially when you've got engine dynos and testing methods to verify results.
Let’s spice this up a bit. If I ventured away from Red Line and wanted a high moly off the shelf oil in a 5w30 flavor to few this turbo engine, what would you all pick and why?
"High moly" reminds me of lique moly,Choose A3B4 certified oil with hths greater than 3.5 for better protection in high temperature conditions
 
It's simple. The engineering, add packs, and chemical makeups of 20wt oils are stronger than you're willing to believe. You also seem to forget there are multitudes of ways to control and remove heat from an engine.... Pro Stock engines run 0W5 oil, and turn 10k+ rpm and make nearly 7 times the power of the Subaru. Here's some science for you:


Hence, with upgrades to 20wts thru things like dexos1 Gen 2 requirements, along with other strict tests for durability, it's certainly possible to run a thinner oil, especially when you've got engine dynos and testing methods to verify results.
I have encountered an engine BOOM using BRZ with OEM oil on the track. After the dealer’s disassembly, it was found that the lubrication capacity of the oil was insufficient, which caused the crankshaft bush to not be effectively lubricated and the connecting rod broke.
 
So, I have an Onyx XT on order. It should be here in a month or two. With the change to SP rated oil and it being compatible with SN Plus, I have a couple questions:

Is the genuine OEM Subaru synthetic identical to the Idemitsu 0w-20 they offer as well? I know Idemitsu manufactures the Subaru oil, but I don’t know if they are identical or not. The new Idemitsu stuff is listed as SP.

If they are the same product, is there a true benefit to using SP over SN plus, or is there a way to make sure my dealer uses the SP? Is the bulk oil they use a problem?
 
So, I have an Onyx XT on order. It should be here in a month or two. With the change to SP rated oil and it being compatible with SN Plus, I have a couple questions:

Is the genuine OEM Subaru synthetic identical to the Idemitsu 0w-20 they offer as well? I know Idemitsu manufactures the Subaru oil, but I don’t know if they are identical or not. The new Idemitsu stuff is listed as SP.

If they are the same product, is there a true benefit to using SP over SN plus, or is there a way to make sure my dealer uses the SP? Is the bulk oil they use a problem?
When I contacted SoA in Dec 2019, they advised me that the Subaru Certified oil met SN+/dexos 1 Gen 2. I was a bit skeptical since a VOA on the 5W-30 posted here showed calcium levels a bit higher than the typical SN+ dexos oils.

Are you asking if the current Idemitsu SP oil is the same as the Subaru Certified oil? I have a feeling it’s not but would be curious to know what is on the label. Even if your dealer is using SN+, I doubt it’s a problem for our cars. The current Idemitsu SP isn’t considered their “Premium” offering. Maybe they’re waiting for dexos 1 Gen 3 to reformulate the premium oil. 🤷‍♂️
 
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This is all you came to deliver? Strong! Confirmation bias? Hardly! If you think I am here to push a product you are very wrong.

PimTac is just trying to raise Message count...Don't let it bother you :)

I would use Mobil 1 ESP 0w40 instead of Redline.
 
It's simple. The engineering, add packs, and chemical makeups of 20wt oils are stronger than you're willing to believe. You also seem to forget there are multitudes of ways to control and remove heat from an engine.... Pro Stock engines run 0W5 oil, and turn 10k+ rpm and make nearly 7 times the power of the Subaru. Here's some science for you:


Hence, with upgrades to 20wts thru things like dexos1 Gen 2 requirements, along with other strict tests for durability, it's certainly possible to run a thinner oil, especially when you've got engine dynos and testing methods to verify results.

Still not explaining the original question, only quoting information that pertains to race cars. Do you really think a Subaru Outbacks engine performs the same as a pro stock car that gets torn down about every 5-6 runs? This should be a simple question yet nobody, not even Subaru will answer it.
 
Still not explaining the original question, only quoting information that pertains to race cars. Do you really think a Subaru Outbacks engine performs the same as a pro stock car that gets torn down about every 5-6 runs? This should be a simple question yet nobody, not even Subaru will answer it.

Love your post. No one ever saw a Pro stock race car engine with 200,000 plus miles on it.
 
When I contacted SoA in Dec 2019, they advised me that the Subaru Certified oil met SN+/dexos 1 Gen 2. I was a bit skeptical since a VOA on the 5W-30 posted here showed calcium levels a bit higher than the typical SN+ dexos oils.

Are you asking if the current Idemitsu SP oil is the same as the Subaru Certified oil? I have a feeling it’s not but would be curious to know what is on the label. Even if your dealer is using SN+, I doubt it’s a problem for our cars. The current Idemitsu SP isn’t considered their “Premium” offering. Maybe they’re waiting for dexos 1 Gen 3 to reformulate the premium oil. 🤷‍♂️

exactly this. If the best quality oil is SP, that’s what I want to run. It is designed for gasoline direct injection turbos and to reduce carbon deposits and timing chain wear. So if it is the same cost in the end, I want the superior product. I will call and see if they can send me their data sheet or specs on the official Subie stuff. I figured it could be the same thing since they make the oil for Subaru.
 
So I guess no one can agree but most say to follow the manual and use 0W20. Mobil1 EP has been my go to oil as of late. I have a 2021 XT Touring Outback that is scheduled to arrive in May.
 
So I guess no one can agree but most say to follow the manual and use 0W20. Mobil1 EP has been my go to oil as of late. I have a 2021 XT Touring Outback that is scheduled to arrive in May.

I think there was quite a bit of agreement in this thread?
 
What was the agreement?
I agree it's a bit hard to discern given Schwifty the troll's attitude. But now that he's gone from this older thread, something with at least a 3.2 HT/HS seemed to be the consensus. One can't go wrong here by using an oil with that HT/HS, right?

At least from my perspective.
 
My brain hurts from reading this back and forth. OP, 30 weight oil in a 20 weight spec’d car will give you no appreciable benefit or detriment (beyond a very small fuel economy hit), stick with it if it makes you happy.
 
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