High performance (800hp+) for winter and summer - Audi 4.0t

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Sounds like the Amsoil websites out there that like to imply that synthetic base stocks are better for alcohol fuels but don’t give a corresponding technical reason why. They do describe fuel dilution issues however. No one here except you has mentioned an “obscene” increase in grade.

I’m still a little confused on why one oil is better than another here. Now you’re saying the real problem is water in the oil? Isn’t that also directly related to proper crankcase breathing and getting the oil up to temp? How’s that different from fuel dilution?
 
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We have technical white papers as to why synthetic base stocks are better for an engine in general. If you're going to put money into aftermarket parts and tune the engine for high performance, why would you not use them? Your line of reasoning/playing devil's advocate here is stupid.

I recommended at least four oils, as I don't play favorites with the top level formulators, they're all good.

I said also, if you'd go back and read it again, maybe you'd comprehend it more. Condensation is an issue, yes. One that is again solved by the oil reaching operating temp, just like your infamous "fuel dilution" problem.
 
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We have technical white papers as to why synthetic base stocks are better for an engine in general. If you're going to put money into aftermarket parts and tune the engine for high performance, why would you not use them? Your line of reasoning/playing devil's advocate here is stupid.

I recommended at least four oils, as I don't play favorites with the top level formulators, they're all good.

I said also, if you'd go back and read it again, maybe you'd comprehend it more. Condensation is an issue, yes. One that is again solved by the oil reaching operating temp, just like your infamous "fuel dilution" problem.
Yeah okay well make it personal and call me stupid, but that’s typically what people do when they no longer can make a cogent technical argument.

Starting to sound like a bunch of nonsense to me and not based on anything of substance.
 
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Yeah okay well make it personal and call me stupid, but that’s typically what people do when they no longer can make a cogent technical argument.

Starting to sound like a bunch of nonsense to me and not based on anything of substance.

You clearly struggle with reading comprehension. I said your line of reasoning and playing devil's advocate in this thread is stupid, not that you as a person are. I'm answering your questions with real-world facts and data and you're just choosing to ignore them. That's on you homie.
 
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Nice ninja edits btw, I'll make sure to quote you from here on out. It was recommended to run a 10w60 weight if on alcohol fuel by another user. Go back and read.
 
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Hello it’s been a while since I ran a high turbo euro direct injection car and want to ask for some advice.

Car is Audi A8 4.0 twin turbo, just installed upgraded turbos and software and about to turn up the boost, targeting 35-40psi and 800whp+.

I using German/Belgian Castrol 0w40 and live in the lovely snowy northeast (sarcasm).

Car is know for bearing wear under these power levels and I would like to improve bearing life.

Can anyone recommend me an upgrade? Should I run a 5w50 in winter and 15w50 in summer or 5w50 all year? Any brand I should look for? I used to run Rotella T6 5w40, would that be a better option? Any advice would help.
Well, as you are living in the snowy north, in such a pushed engined, I would put 5W-40 during winter, or maybe an Euro 5w-30, as the HTHS is rather the same (3.5cP).
For the summer, as this engine might get terribly hot, I would rather put some 20W-50 or even 25W-60, as these are usually thicker than a 5W-50, with far better NOACK.
 
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Well, as you are living in the snowy north, in such a pushed engined, I would put 5W-40 during winter, or maybe an Euro 5w-30, as the HTHS is rather the same (3.5cP).
For the summer, as this engine might get terribly hot, I would rather put some 20W-50 or even 25W-60, as these are usually thicker than a 5W-50, with far better NOACK.

And here again for you @kschachn
 
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To be noted, we would recommend 5000 mile changes on most of these vehicles, mostly because ethanol does leech ZDDP out of the oil and into the breather system, and obviously we didn't want these highly loaded engines depleted of the proper additive package to keep them alive, especially if they were running journal bearing turbos.
You just answered you own question. Ethanol does instant damage to the oil, its not like fuel that burns off. Its already oxidized and damaged the oil before its burnt off. Do some UOA's on these turbo charged cars you have worked with.

In my post I was also considering that the engine will be running two larger turbo's and 100% over stock HP with a performance tune on e85 I would guess.

 
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You just answered you own question. Ethanol does instant damage to the oil, its not like fuel that burns off. Its already oxidized and damaged the oil before its burnt off. Do some UOA's on these turbo charged cars you have worked with.
Read through that one. 6% dilution is massive and not consistent with engine operation. They also never tested the oil in an actual engine where it could get to temp.

I agree that ethanol does have higher oxidation rates than gasoline, so it will kill TBN faster. Doesn't mean the oil won't stay in grade or that you need to jump from a 40 to a 60.

Here's a better study IMHO.
 
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But why is the important bit.
Because they didn't break down? Because the fuel dilution didn't drop them 20 viscosity grades like ya'll are suggesting? Because fuel dilution is mostly solved by temperature and oxidation is the real enemy of oil longevity in an alcohol fueled application?
 
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Because they didn't break down? Because the fuel dilution didn't drop them 20 viscosity grades like ya'll are suggesting? Because fuel dilution is mostly solved by temperature and oxidation is the real enemy of oil longevity in an alcohol fueled application?
I don't think a 800whp modified twin turbo car is aligning with the test procedure carried out in that study. Which is:

'Such method of proceeding is predicted in numerous test procedures, including those developed under the CEC and is intended to reflect average engine operating conditions during a vehicle operation in low-volume urban traffic'.

'The engine lubricating oil was tested on an engine re-search-test bed Ford 1.8L Duratec-HE PFI FFV'.
 
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I don't think a 800whp modified twin turbo car is aligning with the test procedure carried out in that study. Which is:

'Such method of proceeding is predicted in numerous test procedures, including those developed under the CEC and is intended to reflect average engine operating conditions during a vehicle operation in low-volume urban traffic'.

'The engine lubricating oil was tested on an engine re-search-test bed Ford 1.8L Duratec-HE PFI FFV'.
The only difference is more fuel being burned and more engine load. The fuel is still going to evaporate out of the oil. There will be a higher acid load due to more combustion byproducts, but not more fuel dilution because... it evaporates. What little clings to the detergents isn't going to take the oil out of grade.

Once again, grade should be determined by bearing clearance. Maybe this engine can handle a 50 weight, but I'd bet money a 60 is just going to spike oil temp and not provide any better protection. We've seen the real life examples in the BMW V10s. If the clearance doesn't allow room for the oil film thickness the oil wants to create, it simply makes it harder to pump, slows flow, and is subject to more sheer.
 
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This is pretty informative thread even for a guy like me that has vehicles with 1/3 of the power. I am not disregarding anything being said here and I have now expertise in highly modded engines like this. Just some questions that popped into my head.

Don't most high hp super cars use 0w40 as standard and recommend an Xw50 or Xw60 for track use? I know that's different than what this discussion is referencing since high performance auto makers designed the engine and know what the engines requirements are in a factory high performance engines.

But depending on driving style, wouldn't a 0w40 with Porsche or AMG certifications be more than enough to handle most driving habits? Even if it was occasionally being tracked, auto-x, drag strip or the random nights of street racing in Mexico I would assume 0w40 would handle it. But under those circumstances just change the oil more frequently like one naturally should in a high performance vehicle.

Personally I prefer 0wXX oils over 5wXX or 10wXX oils. From my understanding 0wXX oils tend to be more stable due to the base oils needing to be of higher quality to meet those standards. I could be wrong, let me know if I am. I also hail from the midwest where temps range from -25F to 100F which is also why I prefer 0wXX so I don't have to worry about a winter oil and summer oil.
 
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