Ester-based oils? Interesting tech - READ!

[TDIMeister]

Hello all,

I attended the DEER (Directions in Engine-Efficiency and Emissions Research) Conference in Detroit, MI two weeks ago and listened to a fascinating presentation titled, "Low-Reactivity Lubricants for High Efficiency, Spark Ignited Engines" by Terry Alger at Southwest Research Institute.

He asserted that different oil base stocks have different reactivities and when they are present in the combustion chamber have an effect in spark-ignition engines like an effective octane number. He showed his experiments with different base stocks in specially blended lubes as well as retail off-the-shelf ones (but unfortunately did not name them). He showed that a substantial difference in knock-limited ignition timing advance can result simply with different oil base stocks, with ester-based oils being the best in this regard; Group III severely-hydrotreated oils being middle-of-the-pack but I don't remember exactly which fared worst, although PAO comes to mind. The implication here is that just oil selection can allow for running more knock-timing advance, and a modest but not insignificant fuel efficiency and performance improvement can result.

The 2011 paper has not yet been released to the public, but when it is, will be freely available by following the links from the DEER website.

So my question is whether there is a suitable oil out there I can buy that has a substantially ester-based composition without PAO that I can try in my Audi S4? I spoke with the author of the paper and exchanged correspondences; he would only let that the commercial ester-oil he tested was for an aviation application and he did not deny or confirm when I suggested Mobil Pegasus1.

I have generally run Mobil1 of different viscosities depending on season, and actually Diesel oils in my gasser S4 like Mobil1 TDT, Shell Rotella T6 and Castrol Syntec 5W-40.


Thanks

 

[chubbs1]

Redline; Motul if it is under warranty, would be good places to start. Esters are good but there are a lot of factors involved and pros and cons with every lube.

 

[OilNerd]

Originally Posted By: TDIMeister
... The 2011 paper has not yet been released to the public, but when it is, will be freely available by following the links from the DEER website.
...


To quote a Tom Petty and Heartbreakers song, "The Waiting is the Hardest Part."

 

[mechtech2]

Do you presently need spark retard?
Do you really need any addition oil benefits in this regard?

I wonder how oils can substantially affect the 'net' octane requirements.
If the oil on the cylinder walls burns, you have no lubrication and the engine seizes. Is it then simply the presence of oil while combustion takes place? Is it a slight vaporization of the oil that does this?

When the term "substantial" is used to describe the effects, it makes me take notice. I have to respect the study, but I have not found oil to make any difference with spark knock. It may in certain circumstances, of course, but why haven't amateurs/civilians taken notice so far?

 

[TDIMeister]

Most modern cars have knock sensors and adaptive ignition timing to get the most advance before incipient knock and back off to get optimum fuel efficiency.

By substantial, the difference was in the order of 3° between the best- and worst-performing samples investigated, if memory serves. So, maybe not much in the scheme of things, but the difference found in this research cannot be dismissed as negligible.

As for my own car's lube oil needs, I'm quite familiar as a 12-year member and moderator at TDIClub how the subject of oils can arouse so much passion

. I run a good, branded Group III or better oil and change it at appropriate -- not anal-retentive -- intervals. My attitude is, "Drive more, worry less."

 

[gathermewool]

Wouldn't there have to be sufficient oil consumption for this to matter? I know a lot of turbo Subies burn oil, but I don't at all (negligible, if you'd like to be picky,) even up to 7,500 mile intervals.

In my application, it seems that the potentially octane-lowering, mostly PAO Amsoil that I run would not be detrimental compared to, say, Redline. Regardless, I have zero learned knock, running an aftermarket, 93-octane-specific tune.

 

[BobFout]

Good to see you on this side, 'Meister.

Any word on this effect with compression ignition timing?

 

[bluesubie]

I would think that an ester blended with PAO and/or Group III would outweigh ANY other benefits for a passenger car. Where's Tom?

Quote:
Nevertheless, esters are often used in combination with PAOs in full synthetic motor oils in order to balance the effect on seals, solubilize additives, reduce volatility, and improve energy efficiency through higher lubricity. The percentage of ester used can vary anywhere from 5 to 25% depending upon the desired properties and the type of ester employed.


Esters in Synthetic Lubricants.

Just run Red Line, Motul 300V/X-lite, or Renewable Lube Inc and be done with it.

-Dennis

 

[Pablo]

So what about all the PAO's in Redline?

I can see the amateurs using this as Amsoil hate bait. IMHO, it has no real implications in automotive oils.

 

[A_Harman]

Originally Posted By: TDIMeister
He showed that a substantial difference in knock-limited ignition timing advance can result simply with different oil base stocks, with ester-based oils being the best in this regard; Group III severely-hydrotreated oils being middle-of-the-pack but I don't remember exactly which fared worst, although PAO comes to mind. The implication here is that just oil selection can allow for running more knock-timing advance, and a modest but not insignificant fuel efficiency and performance improvement can result.


Was he doing his testing at WOT conditions, or at part-load? For road-load conditions in passenger cars, it seems like optimum spark advance would be reached before knock became a concern.

 

[ammolab]

[/quote]Was he doing his testing at WOT conditions, or at part-load? For road-load conditions in passenger cars, it seems like optimum spark advance would be reached before knock became a concern.[/quote]

And was his engine re mapped to achieve more timing advance to take advantage of this "oil induced" octane effect? I ran my twin turbo 2000 Audi S4 on 87 octane gas for LONG interstate trips. The timing log did not show that I was pulling advance at part throttle cruse. Gas mileage was the same as 93 Octane under the same conditions.

 

[dparm]

I have been running Motul 300V in my Audi S4 for a while. I can't say it runs any better or worse than it did with a group III+.

 

[boxcartommie22]

there are very little pao's in red line!!! and no pao's in motul 300v oils/ per red line and motul..this has been beat to death before...

 

[boxcartommie22]

there are very little pao's in red line!!! and no pao's in motul 300v oils/ per red line and motul..this has been beat to death before...infact, i just spoke to dave at red line "our oils are a grp 5 ester oil" i just wanted to make sure i was correct.

 

[TDIMeister]

Thanks tommie, I'll look into Redline and Motul. I like Redline - loved MTL for my VW gearbox and the power steering fluid is an excellent replacement for Pentosin in the Audi central hydraulic system.

 

[boxcartommie22]

your welcome...anytime..if you want motul you can order it from competitive edge 1-805-237-8911 very fast service!!they have all motuls oils.

 

[TDIMeister]

Originally Posted By: BobFout
Good to see you on this side, 'Meister.

Any word on this effect with compression ignition timing?
A little too quiet for your liking at the F&L section at TDIClub? LOL.

Another interesting presentation from Oak Ridge National Labs about ionic fluids as lubes, but this is still in very early research, not something that can be purchased in stores. Claims significant metal affinity and friction reduction in all regimes - boundary-, mixed- and hydrodynamic lubrication. Seems that much of the benefits can be obtained with additive doses in conventional oils.

 

[mechtech2]

Originally Posted By: TDIMeister
Most modern cars have knock sensors and adaptive ignition timing to get the most advance before incipient knock and back off to get optimum fuel efficiency.

By substantial, the difference was in the order of 3° between the best- and worst-performing samples investigated, if memory serves. So, maybe not much in the scheme of things, but the difference found in this research cannot be dismissed as negligible.

As for my own car's lube oil needs, I'm quite familiar as a 12-year member and moderator at TDIClub how the subject of oils can arouse so much passion

. I run a good, branded Group III or better oil and change it at appropriate -- not anal-retentive -- intervals. My attitude is, "Drive more, worry less."


Many people don't realize how the spark retard works.
There is an upper limit by the mapping/tuning of the computer. You never get more - there is a limit. This is the goal - to utilize all that is there.
Maximum efficiency is NOT by retard! Where in the world did you get that idea? The opposite is true!
The car should not need that retard from the KS unless there is a problem, or a wrong grade of fuel is used.

 

[TDIMeister]

Originally Posted By: mechtech2
I wonder how oils can substantially affect the 'net' octane requirements.
If the oil on the cylinder walls burns, you have no lubrication and the engine seizes. Is it then simply the presence of oil while combustion takes place? Is it a slight vaporization of the oil that does this?
Reactivity effects of engine oil is not predicated on any substantial burning of the oil itself to have its effect on knocking, any more than usual consumption in a modern engine.

 

[TDIMeister]

Originally Posted By: mechtech2
Originally Posted By: TDIMeister
Most modern cars have knock sensors and adaptive ignition timing to get the most advance before incipient knock and back off to get optimum fuel efficiency.

By substantial, the difference was in the order of 3° between the best- and worst-performing samples investigated, if memory serves. So, maybe not much in the scheme of things, but the difference found in this research cannot be dismissed as negligible.

As for my own car's lube oil needs, I'm quite familiar as a 12-year member and moderator at TDIClub how the subject of oils can arouse so much passion

. I run a good, branded Group III or better oil and change it at appropriate -- not anal-retentive -- intervals. My attitude is, "Drive more, worry less."


Many people don't realize how the spark retard works.
There is an upper limit by the mapping/tuning of the computer. You never get more - there is a limit. This is the goal - to utilize all that is there.
Maximum efficiency is NOT by retard! Where in the world did you get that idea? The opposite is true!
Ummm excuse me, that's where I and the cited research was going all along! The control system *tries* to advance timing to mapped MBT values for best efficiency/power until it's forced to retard by incipient knock. Most high-output, high-compression or forced-induction engines cannot maintain MBT timing at all times because of transient effects, etc. Modern ignition systems are constantly adapting to reached mapped MBT values, but cannot maintain those values at all times. You don't need to be anywhere near WOT to be at the knock-limit. Transient load changes alone at very moderate road-loads can cause knocking in some cars. Ammolab above can log requested and actual timing in his car on a normal driving route with some moderate acceleration and he'll see the action going on.