VII Calculation

[OilUzer]

Oil companies list the vi and i am assuming they do not list the amount of vm in a given oil (proprietary info?). I don't recall those numbers being discussed here...

beside the point but also it seems like that these days, vii are not as evil as they used to be when I joined the bitog or maybe it's my perception ...

Q:
Anyways, just curious if the vii (vm) amounts are published and if not, can it be calculated or reverse engineered using other known parameters for example the vi, base oil (mixture percentages) , hths, kv40, kv100, noack, etc.

 

[Snagglefoot]

Good topic. There used to be this intuitive feeling out there that somehow smaller spreads in viscosity makes a "better" oil such as 10w30 vs 5w30 or 15w40 vs 5w40 vs 0w40. I'm wondering if the VII issue is much less important these days. I noticed a large fan boy club for Castrol 0w40, totally bypassing 5w40 on the way down.

I'm starting to think there is no harm in the Xw number being 0, but let's hear all the Perts and Ex-perts give us the goods.

 

[shanneba]

I haven't seen any oils that indicated the actual VM data.
How much is required may vary based on the base oil viscosity, maker and actual additive used.

Exxon Mobil does have a "synthetic lubricant base stocks formulations guide" available that shows how to formulate various API SN oils using their base stocks and Infineum additives.

https://www.exxonmobilchemical.com/en/library/Asset/C3CD9A982A2F44F6858754AB7DF384D1

Using various amounts of Exxon PAO base oil with approx 4,6, and 8 viscosity @ 100C the %weight of Infineum VM used :

0w-20 2.6%
0w-30 7.0%
0w-40 11.6%


5w-30 2.8%
5w-40 8.7%
5w-50 11.6%
10w-60 14.4%

They also show a formulation using thinner PAO base stocks (5w-30) with Synesstic AN base stocks.
Both the 5w-30 and 5w-40 show VM % of 8.5 in this formula.

The Syn AN base oil shows better oxidative stability, seal swell and deposit control. It also shows significantly reduced cam wear according the Exxon Mobil.

 

[SonofJoe]

Back in the day, I built myself a simple but effective engine oil blending program in Lotus 123. You could put together all the various bits of an oil & it would tell you stuff like KV100, KV40, CCS, KV after KO30, HTHS, Noack, TBN, metals, nitrogen, sulphur & most important of all, it's cost.

If say I wanted to find out what The Competition was doing, I'd get hold of some oil, get it checked out in the lab & then try and make a Chinese copy of the oil in Lotus. You never knew if the copy was correct but my gut feel was they they were always close enough to get some kind of insight. Interestingly it was often the type & amount of VII used by The Competition which I was particularly curious about.

 

[benjy]

a very interesting + gray topic for sure. take a 30W PAO its said to meet the 10-30 spec without any VII's + i have seen the smaller is better spread many times but base oils used are not mentioned. its also noted oil specs are listed for a new virgin finished oil with the ad pack, + the kicker is how cheaper base oils degrade quickly as well as cheaper VII's + many air + oil only cooled big V-twin or high power crotch rockets with shared engine oil used in their transmissions note poor shifting in as little as 1 or 2 thou as a cheap oil is quickly destroyed!!

 

[dailydriver]

Originally Posted by SonofJoe
Back in the day, I built myself a simple but effective engine oil blending program in Lotus 123. You could put together all the various bits of an oil & it would tell you stuff like KV100, KV40, CCS, KV after KO30, HTHS, Noack, TBN, metals, nitrogen, sulphur & most important of all, it's cost.

If say I wanted to find out what The Competition was doing, I'd get hold of some oil, get it checked out in the lab & then try and make a Chinese copy of the oil in Lotus. You never knew if the copy was correct but my gut feel was they they were always close enough to get some kind of insight. Interestingly it was often the type & amount of VII used by The Competition which I was particularly curious about.


Many (most??) on here still think that any amount of any type of VII is "EVIL plastic", and to be avoided, at all costs due to shearing, etc.

IS that the 'truth', or are there actually modern/'high tech' VII formulations which are NOT all that shear-prone, nor harmful 'evil plastics' as thought on here, and maybe even actually quite beneficial, even if quite co$tly in dollar amount?

 

[SonofJoe]

Originally Posted by dailydriver
Originally Posted by SonofJoe
Back in the day, I built myself a simple but effective engine oil blending program in Lotus 123. You could put together all the various bits of an oil & it would tell you stuff like KV100, KV40, CCS, KV after KO30, HTHS, Noack, TBN, metals, nitrogen, sulphur & most important of all, it's cost.

If say I wanted to find out what The Competition was doing, I'd get hold of some oil, get it checked out in the lab & then try and make a Chinese copy of the oil in Lotus. You never knew if the copy was correct but my gut feel was they they were always close enough to get some kind of insight. Interestingly it was often the type & amount of VII used by The Competition which I was particularly curious about.


Many (most??) on here still think that any amount of any type of VII is "EVIL plastic", and to be avoided, at all costs due to shearing, etc.

IS that the 'truth', or are there actually modern/'high tech' VII formulations which are NOT all that shear-prone, nor harmful 'evil plastics' as thought on here, and maybe even actually quite beneficial, even if quite co$tly in dollar amount?

VIIs are not, and never have been 'EVIL plastic'. In fact, after ZDDP, I'd rank them as THE most useful & effective of all the engine oil additives.

VIIs basically ushered in the age of true multigrade oils at a time when almost all base oils were lowish Viscosity Index Group I minerals. They yield oils that are thin enough to pump at low temperatures & thick enough to limit wear at high temperatures.

It's true that Group IIIs & PAOs have higher VI than minerals but the increase only PARTIALLY reduces the need for VII; it seldom eliminates it altogether. Having a VII-free PAO based 10W30 might be seen as being 'pure' but it's not really going to cut it, if for example, you're trying to drive when there's a polar vortex running riot outside!

One has to be careful about demonising certain aspects of oil additives and at the same time, wilfully ignoring the greater benefit they bring. You could easily pick on overbased metallic detergents because they put about 1% of what is basically chalk (calcium carbonate) into oil.

Also VII is not the only 'plastic' in oil. Bis-succinimide ashless detergents based on 2100 MWt Poly Iso-Butylene are so viscous they never exist in their pure state. Instead they tend to only exist as 50% dilutions with thin base oil!

 

[burla]

Take the operating viscosityand hths into consideration. If cSt is equal then your higher hths will have less vii's.

 

[dailydriver]

Originally Posted by SonofJoe
Originally Posted by dailydriver
Originally Posted by SonofJoe
Back in the day, I built myself a simple but effective engine oil blending program in Lotus 123. You could put together all the various bits of an oil & it would tell you stuff like KV100, KV40, CCS, KV after KO30, HTHS, Noack, TBN, metals, nitrogen, sulphur & most important of all, it's cost.

If say I wanted to find out what The Competition was doing, I'd get hold of some oil, get it checked out in the lab & then try and make a Chinese copy of the oil in Lotus. You never knew if the copy was correct but my gut feel was they they were always close enough to get some kind of insight. Interestingly it was often the type & amount of VII used by The Competition which I was particularly curious about.


Many (most??) on here still think that any amount of any type of VII is "EVIL plastic", and to be avoided, at all costs due to shearing, etc.

IS that the 'truth', or are there actually modern/'high tech' VII formulations which are NOT all that shear-prone, nor harmful 'evil plastics' as thought on here, and maybe even actually quite beneficial, even if quite co$tly in dollar amount?

VIIs are not, and never have been 'EVIL plastic'. In fact, after ZDDP, I'd rank them as THE most useful & effective of all the engine oil additives.

VIIs basically ushered in the age of true multigrade oils at a time when almost all base oils were lowish Viscosity Index Group I minerals. They yield oils that are thin enough to pump at low temperatures & thick enough to limit wear at high temperatures.

It's true that Group IIIs & PAOs have higher VI than minerals but the increase only PARTIALLY reduces the need for VII; it seldom eliminates it altogether. Having a VII-free PAO based 10W30 might be seen as being 'pure' but it's not really going to cut it, if for example, you're trying to drive when there's a polar vortex running riot outside!

One has to be careful about demonising certain aspects of oil additives and at the same time, wilfully ignoring the greater benefit they bring.


THANK YOU!

There was a member on here who was quite 'demonized', and viewed as a pariah on here for believing that there WERE actually very good, all but shear-proof, modern high tech VIIs existing out there, which were used in some of the the top grade, (and highest VI spec) oil formulations.