RAVENOL USVO VST 5W-40 any other oil on the market that is better ?

So what does that mean?
Meaning that it has detergent/dispersant properties more suitable than 300V for street use. Probably mix of base stock to limit oxidation etc. But, it has high HTHS which you obviously want, but also that HTHS limits which approvals can pass (it is questionable whether it could pass MB229.5 or BMW LL01). Why bothering getting MB229.3 since it is outdated (Mobil1 does that though). It is Ester based, so highly doubt oxidation is suitable for LL01. So why bothering with approvals? They developed oil for people who want dual use, but maximum protection at track. At that point warranty is irrelevant. It is targeted for customers that are more knowledgeable about oils than regular drivers.
I am actually strongly considering this oil for my BMW since it will see track.
 
Meaning that it has detergent/dispersant properties more suitable than 300V for street use. Probably mix of base stock to limit oxidation etc. But, it has high HTHS which you obviously want, but also that HTHS limits which approvals can pass (it is questionable whether it could pass MB229.5 or BMW LL01). Why bothering getting MB229.3 since it is outdated (Mobil1 does that though). It is Ester based, so highly doubt oxidation is suitable for LL01. So why bothering with approvals? They developed oil for people who want dual use, but maximum protection at track. At that point warranty is irrelevant. It is targeted for customers that are more knowledgeable about oils than regular drivers.
I am actually strongly considering this oil for my BMW since it will see track.

Thank you for the clarification!


I can see some dismissed this oil yet no one has posted a 5w40 with better numbers than the Motul Sport 5W40 has (HTHS 4.0 and noack 4.7) I know these two parameters are not the only ones that matter , for a good engine oil but still can someone please post a 5W40 with better HTHS and noack ?

Oh and my car is a Turbo Subaru the only requirement in the manual is API SN/SM....that this oil meets according to Motul.... so how is this not an awesome oil, I still don't understand ?

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Redline 5W40 looks good but 5l here costs £87 .....for the Motul 5l I paid £43
 
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That's easy, the awesome is in the fixation and not in these oils. The reason for your choice of the 5W-40 grade simply remains unclear when you're primarily after negative Noack and maximum HTHS. HTHS is nothing but another viscosity figure (representing some behaviour under medium shear rates and temperatures). Will cost some fuel and rob some power. Same with Noack, if the figure is four, six or eight won't make for an impressive oil. Let your Subaru add some fuel to it and the figure is a new one anyway as it's only a weight loss from some lighter fraction leaving a big narrative ,-)
 
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That's easy, the awesome is in the fixation and not in these oils. The reason for your choice of the 5W-40 grade simply remains unclear when you're primarily after negative Noack and maximum HTHS. HTHS is nothing but another viscosity figure (representing some behaviour under medium shear rates and temperatures). Will cost some fuel and rob some power. Same with Noack, if the figure is four, six or eight won't make for an impressive oil. Let your Subaru add some fuel to it and the figure is a new one anyway as it's only a weight loss from some lighter fraction leaving a big narrative ,-)

I got this from the NASIOC forum (quoted below) and most subaru forums recommend looking for high HTHS and low noack for turbo subaru's....unless I'm doing it wrong then I'm all open for suggestions what should I be looking for instead, I'm not very technical or knowledgeable but I'm trying to learn..and I'm not a specific brand fanboy I don't care what brand the oil I'm using is as long as it's very good....

''High Temperature-High Shear Viscosity (HT/HS)
HT/HS is a measure of dynamic viscosity, it represents the oil’s thickness within the vital hydrodynamic bearings of an engine. It is the most important measure of how well the oil will perform as a hydrodynamic lubricant. HT/HS is measured at 150°C (302°F) which is a worst-case temperature for most engines. The higher the HT/HS, the stronger the hydrodynamic film in the engine’s bearings. Thus, the correct HT/HS is more important than the KV100 (SAE Grade) when selecting oil. If the oil formulator publishes their HT/HS it's best to ignore the grade and KV100 and base your choice on the HT/HS. As we will see later, different industry specs categorizing motor oil are based in large part on HT/HS and those specifications will tell us much about the oil's HT/HS even if the formulator doesn't publish a specific value.''
 
I got this from the NASIOC forum (quoted below) and most subaru forums recommend looking for high HTHS and low noack for turbo subaru's....unless I'm doing it wrong then I'm all open for suggestions what should I be looking for instead, I'm not very technical or knowledgeable but I'm trying to learn..and I'm not a specific brand fanboy I don't care what brand the oil I'm using is as long as it's very good....

''High Temperature-High Shear Viscosity (HT/HS)
HT/HS is a measure of dynamic viscosity, it represents the oil’s thickness within the vital hydrodynamic bearings of an engine. It is the most important measure of how well the oil will perform as a hydrodynamic lubricant. HT/HS is measured at 150°C (302°F) which is a worst-case temperature for most engines. The higher the HT/HS, the stronger the hydrodynamic film in the engine’s bearings. Thus, the correct HT/HS is more important than the KV100 (SAE Grade) when selecting oil. If the oil formulator publishes their HT/HS it's best to ignore the grade and KV100 and base your choice on the HT/HS. As we will see later, different industry specs categorizing motor oil are based in large part on HT/HS and those specifications will tell us much about the oil's HT/HS even if the formulator doesn't publish a specific value.''

HTHS is a viscosity characteristic, it isn't bad or good, you want high HTHS, run some sweet straight SAE 60, it'll also have wickedly low Noack ;)

HTHS is, as the article you quoted states, the viscosity under high shear conditions, as the name implies. Engine design plays a huge role in what the lower limit is, while, within reason, there really isn't an upper limit. That said, going well above the lower limit isn't providing cumulative benefit. If your engine requires an HTHS of ~3.0cP to keep the bearings separated under the worst possible conditions, going for a ~4.0cP isn't going to improve anything, it'll just rob power.

A few of the Euro specs, including the ACEA ones mandate a minimum HTHS level. For approvals like A40 and LL-01 that HTHS limit is 3.5cP or greater, which is where the oils you seem to be looking at fall. Note that the spec isn't >3.5cP with a caveat that more is better, it's simply that 3.5cP is the minimum for that approval level and oils will fall within a range above that point with some landing squarely on it. For applications calling for those specs, ANY of those oils will yield performance indistinguishable from each other, which is the entire point.

I assume your application calls for an oil with an HTHS ~3.0cP, so you are already well above that with the oils you are looking at. Are you producing significantly more power than stock? That would be a valid reason to pursue an oil with a higher HTHS for a particular application, but even then, it's not necessarily a requirement. My 6.4L at 475HP calls for the same 0w-40 as the 707HP 6.2L, so does the 840HP version found in the Demon.

On Noack, lower is typically better, but there are manufacturer limits on that as well. I believe Mercedes sets a ceiling of 10%, which all of the oils you are looking at are below. Ravenol and Rowe seem to stand out as offering very low Noack and exceptional cold temperature performance within a given approval set. This is likely due to having mostly PAO bases. With 5w-40's, it's easier to get away with less, or no PAO and using heavier Group III. This will keep Noack low but cold temp performance may be very close to the limits for the Winter designation.
 
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Some all too common misconceptions. The 150°C are by no means a worst case temperature, not meant as such and the whole temperature aspect is secondary to the shear rate aspect the HTHS deals with. Viscosity loss from heat is to some degree countered by the viscosity index improvers, but the gain from this has a tendency to get lost. Lost permanently (the problem of shear stable VII) but more importantly lost each time the oil sees high shear rates (the shear rates of one million per second that the HTHS figure deals with represents idle only! in some areas in some cases, so again no worst case).

But it would be true to accept HTHS-viscosity as the primary viscosity figure to have in the running engine. And as such, it remains a viscosity figure that better not became higher and higher, if from oil degradation or from inadequate oil choice. You had no tendency to end up with some SAE 70 and for about the same reasons should not need to end up with HTHS of 7 when the car may expect something like 3 perhaps. Over some 5W-30 SN/CF the mentioned HTHS of 3.7 could probably mean a reasonable extra dose.
I cannot comment on these engines, no idea if there's a deficit. But higher HTHS can only compensate for some defict. It's not leading to "stronger the hydrodynamic film in the engine’s bearings". And not even the film thickness will become greater and wiser and ever grown up from upping HTHS as there may be film thickness on the other side of the bearing too :) No HTHS threshold for a grown up MOFT, no sense whatsoever in raising it higher and higher, just as with all the other viscosities or the viscosity grade.

For temporary viscosity at higher shear rates than represented by HTHS this figure can even turn things somewhat upside down between two oils as the gain from VII get's lost. Higher gain, that contributed to HTHS if the oil relied much on those VII, turns into higher temporary viscosity loss from shear.

There are better explanations than this in my bad language. User Gokhan showed lots of illustration, have a look at it.
 
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I think you are barking up the right tree. A higher HTHS and a lower Noack for any given viscosity is not a bad thing it is a good thing. You will also see less VII in true synthetic base oils meaning less shear under racing conditions. If you are racing and need the 10W40 for your Subaru the MOTUL is probably fine if somewhat expensive. If you don't care about manufacturer approvals I say go for it.
 
An ordinary HDEO 10W-30 with HTHS 3.6 ends up thicker at really high shear rates than the 5W-40 with its HTHS of 4 (which is not exactly what people tend to make of such a difference in HTHS).
The Sport Ester 5W-40 looks better than the 5W-50 version with HTHS of 4.5 in the end would. For the same reasons. So it's clear that HTHS remains a figure for 150°C and one million / second only. The straighter 10W-30 ends up even better and that's not told by this NASIOC with its worst case statements. (Of course lower_HTHS_is_better also doesn't apply.)

On the other hand there'd be no sports in these bottles at all if these contained oils that by some magic remained chewy at 20 millions per second. Bad enough what they're costing and wasting in milder areas as they are, but they'd become thinnies on the track under high shear. That's the sports in them.
 
An ordinary HDEO 10W-30 with HTHS 3.6 ends up thicker at really high shear rates than the 5W-40 with its HTHS of 4 (which is not exactly what people tend to make of such a difference in HTHS).
The Sport Ester 5W-40 looks better than the 5W-50 version with HTHS of 4.5 in the end would. For the same reasons. So it's clear that HTHS remains a figure for 150°C and one million / second only. The straighter 10W-30 ends up even better and that's not told by this NASIOC with its worst case statements. (Of course lower_HTHS_is_better also doesn't apply.)

On the other hand there'd be no sports in these bottles at all if these contained oils that by some magic remained chewy at 20 millions per second. Bad enough what they're costing and wasting in milder areas as they are, but they'd become thinnies on the track under high shear. That's the sports in them.

So then a HD oil like this for trucks https://www.opiecommercialoils.co.uk/mobil-delvac-1-le-5w-30-fully-synthetic-engine-oil is better than the Motul one aimed at sports cars for my car?
 
And if we compare the 3 oils in the table below .....how is not MOTUL sport the best out of those 3? I cannot understand? People keep mentioning 10W30 5W50 10W50 but I'm not talking about that I wont use anything other than 5W30 5W40 or 0W40.....I'm talking about the best 5W40 oil with the best noack and HTHS....maybe I'm too stupid to understand? Or are you trying to tell me that as long as the oil meets the minimum HTHS and noack there is no point comparing those characteristics, and I should be looking at something else to determine the best oil for my application? Subaru turbo boxer engines are notorious for shearing oil even under normal driving conditions....that's why i'm looking at HTHS and noack...

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These 3 oils cost about the same here in the UK give or take £3 or £4,,,,
 
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First of all you need to face the fact that HTHS is in no way any insurance against "shear". Not against permanent viscosity loss from shear and not against temporary viscosity loss from shear. Higher gain in HTHS viscosity from polymeric boost in fact means higher temporary viscosity loss at high shear rates. "Shear stable" would only mean good resilience of the VI enhancers themselves so they'd have a longer life but still not be of any help at high shear rates. ->shear thinning

It's not "better", there's no general "better" at all until you try to focus on a few aspects. The best all around would probably be one with higher "natural VI", better FM et al. if you want best protection when you floor it. For areas in the engine seeing high shear rates some kinematic viscosity @100°C in the oil pan is quite irrelevant and HTHS-V still only means a hint. In your table for those three you'd principally want to see the combination of the ROWE's HTHS and the Ravenol's KV100, preferably from "naturally high VI" = not much VI boost.
So, above table basically shows no difference at all and while these oils in fact form a kind of group among all 5W-40s you basically have to believe in them as this group until you make other oils actually look worse in some regard.
https://books.google.de/books?id=l9Vwt7MPzRUC&pg=PA171#v=onepage&q&f=false
shows an exemplary compact table that deals with the articulation of viscosity curves for higher shear rates.

I shall try to fit your oils in Gokhan's worksheet which can be a bit of help looking at it.
 
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Thank u
First of all you need to face the fact that HTHS is in no way any insurance against "shear". Not against permanent viscosity loss from shear and not against temporary viscosity loss from shear. Higher gain in HTHS viscosity from polymeric boost in fact means higher temporary viscosity loss at high shear rates. "Shear stable" would only mean good resilience of the VI enhancers themselves so they'd have a longer life but still not be of any help at high shear rates. ->shear thinning

It's not "better", there's no general "better" at all until you try to focus on a few aspects. The best all around would probably be one with higher "natural VI", better FM et al. if you want best protection when you floor it. For areas in the engine seeing high shear rates some kinematic viscosity @100°C in the oil pan is quite irrelevant and HTHS-V still only means a hint. In your table for those three you'd principally want to see the combination of the ROWE's HTHS and the Ravenol's KV100, preferably from "naturally high VI" = not much VI boost.
So, above table basically shows no difference at all and while these oils in fact form a kind of group among all 5W-40s you basically have to believe in them as this group until you make other oils actually look worse in some regard.
https://books.google.de/books?id=l9Vwt7MPzRUC&pg=PA171#v=onepage&q&f=false
shows an exemplary compact table that deals with the articulation of viscosity curves for higher shear rates.

I shall try to fit your oils in Gokhan's worksheet which can be a bit of help looking at it.

Thanks a lot for the detailed answer, much appreciated!
 
The first lines in this now are from Gokhan's table – I hope I left them unmodified...
Then I brought in the 10W-30 HDEO I had in mind and finally your group of three (with the values from your table).

The column called BO DV150 (base oil's dynamic viscosity) is meant to illustrate something like the oil's viscosity @150°C and high shear rates (as opposed to the medium shear rate in HTHS). This way a different picture is drawn and HTHS can get relativised quite a bit. It's no tool to establish rankings, but HTHS & Noack don't lead to a ranking either. Just an additional perspective.
Our group of three can't be expected to have a foundation from base oils particularly good in natural VI and the "calculator" seems to support the presumption that they'd suffer quite some viscosity loss.

halb.jpg


Screenshot 2020-09-19 151147.jpg

 
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Or are you trying to tell me that as long as the oil meets the minimum HTHS and noack there is no point comparing those characteristics, and I should be looking at something else to determine the best oil for my application? Subaru turbo boxer engines are notorious for shearing oil even under normal driving conditions....that's why i'm looking at HTHS and noack...

Within a given set of approvals, that's the whole idea of the approvals. The outlier here is the Motul, which doesn't have any of the approvals the other two do.

What oil does your engine call for? As I noted earlier, if it calls for, and was tested on, a 5w-30 with an HTHS ~3.0cP you are already going above and beyond with any of these lubricants which are spec'd and approved for much higher density Porsche, Mercedes, BMW, Audi...etc applications that are likely significantly harder on oil than your Subaru.

Porsche A40 consists of simulated lapping of the Nurburgring for an extended duration followed by tear-down and analysis, just as an example.
 
The first lines in this now are from Gokhan's table – I hope I left them unmodified...
Then I brought in the 10W-30 HDEO I had in mind and finally your group of three (with the values from your table).

The column called BO DV150 (base oil's dynamic viscosity) is meant to illustrate something like the oil's viscosity @150°C and high shear rates (as opposed to the medium shear rate in HTHS). This way a different picture is drawn and HTHS can get relativised quite a bit. It's no tool to establish rankings, but HTHS & Noack don't lead to a ranking either. Just an additional perspective.
Our group of three can't be expected to have a foundation from base oils particularly good in natural VI and the "calculator" seems to support the presumption that they'd suffer quite some viscosity loss.

View attachment 29686

View attachment 29685

Thanks for this!

So then it looks like the Motul 8100 X-clean+ 5W30 is better then all the 3 oils I was on about?
 
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