Another Subaru thread?

Schwifty

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Your user manual should have corresponding instructions on the use of engine oil, there will be a recommended viscosity and multiple applicable viscosities.
In fact, most turbine owners in Japan use 5W40 oil

All of my other turbo 4's have used 5w40 as well even though the factory spec'd 5w20 on them. I find it ludicrous to run a 20wt in a hot turbo engine. My manual only states 0w20 SN or SN+ and 5w30 as acceptable top off. Nothing about running it flat out. Which makes me think this book is just recycled from another platform to save money.
 
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All of my other turbo 4's have used 5w40 as well even though the factory spec'd 5w20 on them. I find it ludicrous to run a 20wt in a hot turbo engine. My manual only states 0w20 SN or SN+ and 5w30 as acceptable top off. Nothing about running it flat out. Which makes me think this book is just recycled from another platform to save money.
In fact, the use of 0W20 engine oil is only to obtain lower fuel consumption performance during testing.
To protect the engine, using 0W40 or 5W40 oil is a more reliable choice
 
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There will be a UOA on this oil when I pull it around 2500 miles. ....
We shall see.
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
 

Schwifty

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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


According to a local Subaru speed shop, they said the new FA24DIT is a seriously strong engine and is good for over 500-600 BHP on stock internals. He mentioned that they upgraded the rods, pistons, and it has thicker cylinder walls plus some other stuff. The only thing that limits this engines true potential is the CVT. We chatted about oil for a bit, but his choices really were build dependent, obviously my choice of 5w30 Red Line is overkill and he mentioned using QSUD or Rotella Gas Truck as a daily oil. For their more robust builds they start using Motul and Amsoil or Red Line, but these are monster builds. I'll try to get some UOA's from his different customer builds and see if I can share them. Now if this car has a stout 6 speed standard.... Whoo buddy, I'd be tuning in a hurry that's for sure.
 
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RGT ain't all that. Running it now. Valvoline Advanced was the best "walmart" oil I've run by far.
And I've never liked Valvoline Synpower in the 5W/10W -30 grade.

The New formulation is astounding.

It is REALLY special oil.
 

Schwifty

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RGT ain't all that. Running it now. Valvoline Advanced was the best "walmart" oil I've run by far.
And I've never liked Valvoline Synpower in the 5W/10W -30 grade.

The New formulation is astounding.

It is REALLY special oil.


Can you elaborate on this a bit? Did you have poor UOA's from RTG? What are the spec's and add pack on this Valvoline?
 

Schwifty

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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?
 
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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?
It depends how you define "high moly" and "off the shelf". I recommended a few high HTHS 5W-30's in my reply and I would go that route over picking a favorite metallic additive. Two of the highest HTHS SP/GF6 5W-30's are Motul Eco-lite and Amsoil XL at 3.3. Not sure if the viscosity on those would hold up any better than a lower HTHS 5W-30 after some shearing and/or fuel dilution but the viscosity does hold up better in the FA20DIT on the 3.5+ HTHS oils.


Eneos Racing Street (not really a "racing" oil) does have a robust metallic additive pack but it's not available as a 5W-30. I think there's a VOA on the 0W-20 posted in the VOA forum.
 
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Schwifty

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It depends how you define "high moly" and "off the shelf". I recommended a few high HTHS 5W-30's in my reply and I would go that route over picking a favorite metallic additive. Two of the highest HTHS SP/GF6 5W-30's are Motul Eco-lite and Amsoil XL at 3.3. Not sure if the viscosity on those would hold up any better than a lower HTHS 5W-30 after some shearing and/or fuel dilution but the viscosity does hold up better in the FA20DIT on the 3.5+ HTHS oils.


Eneos Racing Street (not really a "racing" oil) does have a robust metallic additive pack but it's not available as a 5W-30. I think there's a VOA on the 0W-20 posted in the VOA forum.

Ewww 20wt
 
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All great points. Subaru still does have the same owner's manual language that a thicker viscosity is required in high temps, although they do not define the high temps nor the thicker viscosity. But there's not much uoa data out there on this new engine. You can find maybe 2 or 3 uoa's. Someone on the Outback forum did post a 0W-20 uoa from a new XT that dropped to a 16 grade but I think that's to be expected.

The FA24DIT in the Ascent and new Outback/Legacy is supposed to be a more robust engine than the FA20DIT and Prime Motoring in NJ dropped an Ascent engine into a Crosstrek and is making 500+ whp on the stock block. The FA24 has thicker cylinder walls, more cylinder support molded into the casting, thicker rods, and stronger beehive valve springs (see video below). Can these components alone accommodate a lower grade oil? Not sure if bearing clearances have changed.

Back to the OP's question (or statement?). I don't think I'd be running a high SAPS oil in a Subaru DIT. If I used a high HTHS 5W-30, it would be Rotella T6 5W-30 MV, or an ACEA C3 oil, since those add packs would be a bit friendlier in regards to IVD and possible LSPI. There are lots of uoa's on the FA20DIT on nasioc where Resource Conserving 5W-30 showed low uoa wear metals using an oil with the operating viscosity of a 20 grade due to sheared and/or fuel diluted oil. Yes, there are a few posts about dealer serviced WRX's that had engine failure, but not at the level of the EJ's.

IAG Performance actually recommends reduced SAPS Motul X-clean in their built FA20DIT's. They only recommend Motul X-cess in their built EJ's.

Here's a video with some details of the FA24 where they also mention the Prime Motoring swapped Crosstrek.

Some quotes from Prime Motoring posted on nasioc (I think from PM's social media):

[Subaru] used the FA20 as a building block to learn and grow. Every weak or inefficient point on the FA20 has been improved upon.

The rods are still J shaped but way beefier

From what I can see so far, the future STI will be a great one. I was already a fan of the 2.0 but Subaru really improved on the weak areas. Also using FA24 cylinder heads and modifying them to work in an FA20 application. Only aftermarket part used was a set of ARP studs, everything else was new directly from Subaru. Goal of this is through trial and error, advance the FA platform further and give additional options to future customers. We will take it where no FA24 has been before and probably end up in many little pieces but this is the sacrifice we make for the future of Subaru performance

Thanks for the great detail. We can all learn from this.
 
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Can you elaborate on this a bit? Did you have poor UOA's from RTG? What are the spec's and add pack on this Valvoline?
No I didn't like they way it put the power down - It didn't feel weightless and slickery.

You can do bench racing and bench chemist all day long. Try the oil and see how it does.
If the engine gets hurt, then it was junk anyway.

The Valvoline Advanced (not modern engine) was the best 5W30 I've ever run.
And just for comfort it has a stunning "visible" add pack for an ILSAC oil.
 

Schwifty

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How can an engine be "literally the same" when BOTH the bore and stroke have been changed?

its the same platform, nothing else has really changed. What’s so hard to understand here? Do you really think they redesigned the entire engine from the ground up for a simple bore and stroke change and to use a 20wt oil?
 
its the same platform, nothing else has really changed. What’s so hard to understand here? Do you really think they redesigned the entire engine from the ground up for a simple bore and stroke change and to use a 20wt oil?
Engine warranty replacements and lost customers are not cheap. I'm pretty sure the engines have been tested in the most extreme conditions possible with 20wt oil to last a long time. It's got a 60k or longer warranty on it using 20wt oils, so what are you harping about? There's been probably over 200 million miles traveled in turbo cars using 20wt oils.
 

Schwifty

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Engine warranty replacements and lost customers are not cheap. I'm pretty sure the engines have been tested in the most extreme conditions possible with 20wt oil to last a long time. It's got a 60k or longer warranty on it using 20wt oils, so what are you harping about? There's been probably over 200 million miles traveled in turbo cars using 20wt oils.

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.
 
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