Not another thick vs. thin, just test info

[SubieRubyRoo]

Found this in one of the articles on the CIMAC website:

Experiments were completed using a fuel economy test protocol that was defined, consisting of repeating six speed/load operating conditions. An automated dynamometer control system was implemented to ensure repeatability of the test procedure. Preliminary testing indicated that the coolant, oil, and exhaust temperatures reach a steady state within 5 minutes of changing operating conditions. The system oil viscosity was found to have a significant impact on friction, with a reduction in viscosity from SAE 30 to SAE 20 resulting in over 6% reduction in friction mean effective pressure (FMEP) and over a 2% reduction in brake-specific fuel consumption (BSFC). Chemistry effects were also evident in the system and cylinder oils. Repeatability comparisons between the individual repetitions of each operating condition were used to ensure that results are statistically valid. For the initial cylinder oil viscosity experiments, observed changes were within the established/normal repeatability; ongoing experiments will determine whether improvements in boundary condition control will enable cylinder friction changes of this magnitude to be measured on this engine platform.

Sounds great... but 2% of BSFC is an infinitesimally small number, since a 2% reduction in BSFC on a typical high-performance engine would be like saying you reduced the initial BSFC of .5000 lb/(hp⋅h) * .98 = .4900 lb/(hp⋅h).

 

[dnewton3]

Yeah - that's much more difficult to translate into modern cars and trucks.

There's also a proven reduction in friction as the TCB ages; see SAE 2007-01-4133. A 10x reduction (an entire order of magnitude) in valvetrain friction as the TCB develops and matures. But they didn't test that same phenomenon on cylinders ... so who knows what complimentary or off-setting events would materialize.

 

[CR94]

Sounds great... but 2% of BSFC is an infinitesimally small number,...

Do you have a clue what "infinitesimal" means? One dictionary says it means "Immeasurably minute." A 2% reduction in fuel consumption isn't huge, but it's certainly better than infinitesimal.

 

[Jimmy_Russells]

Do you have a clue what "infinitesimal" means? One dictionary says it means "Immeasurably minute." A 2% reduction in fuel consumption isn't huge, but it's certainly better than infinitesimal.

Vehicle that gets 25 mpg average will now average 25.5, using 80 gallons less fuel over 100,000 miles. That’s quite a bit.

 

[SubieRubyRoo]

Do you have a clue what "infinitesimal" means? One dictionary says it means "Immeasurably minute." A 2% reduction in fuel consumption isn't huge, but it's certainly better than infinitesimal.

It appears that sometimes, your sense of sarcasm is infinitesimally small

Most people are prone to slight over-exaggerations of some details, without truly meaning it to the full extent of the word. Sorry.

 

[SubieRubyRoo]

Vehicle that gets 25 mpg average will now average 25.5, using 80 gallons less fuel over 100,000 miles. That’s quite a bit.

No, it won't be 25.5, because that's 2% of the BSFC, NOT 2% increase in mileage.

Also, you would never ever be able to statistically prove the oil alone was responsible for that increase due to varying environment and conditions. kschachn has covered the statistical side of easily disproving a claim like this quite well in many threads.

 

[CanAmAndMore]

Do you have a clue what "infinitesimal" means? One dictionary says it means "Immeasurably minute." A 2% reduction in fuel consumption isn't huge, but it's certainly better than infinitesimal.

Just add 1 more psi to your car tires, and call it a day.

If my car gained or lost 2% MPG or liters per 100 kms, I wouldn't even notice.
Going from a no wind day, to driving into a good head wind is probably a 20% difference.

Someone who notices 2% difference really needs to get a life, they have too much spare time on their hands.

 

[wemay]

5w30 v 0w20

Fuel mileage is better with 0w20. That's not debatable and is proven. But you will not notice it in real world driving.

Wear is less with 5w30. That's not debatable and is proven. But you will not notice it in real world driving.

I feel like I keep getting snagged by drift nets on this topic.

 

[dnewton3]

Also, you would never ever be able to statistically prove the oil alone was responsible for that increase due to varying environment and conditions. kschachn has covered the statistical side of easily disproving a claim like this quite well in many threads.

I could not agree more.

My experiences in working in quality labs and engineering development leads me to believe that most tests flat out ignore the topic of variation which in the real world. What happens with great frequency is that one or two lab tests are run and then they "model" the expected typical results using computer driven projections. While this is reasonably "good enough", it lacks validation many times.

Example:
I was asked to test two competing brand components for use in a cooling system. I was told to go run a couple back-to-back tests with each competing component. I did so, against my objections, and the results showed the two were "essentially equal" and management was happy. I asked the engineering management a few questions ...
- Hey guys, what's the gauge RnR on this test equipment? They had no clue.
- Hey guys, what's the variation of each single component in micro-analysis? They didn't know.
- Hey guys, what's the variation of each brand in macro-analysis? They didn't have an answer.
So they had no idea how accurate the test results were, how well any one specific component could produce the same result, and how likely it was that a production assembly system would produce the same result. They were just wanting to get some single-sample results and then model everything on computers after that.

One of my biggest pet-peeves is how trusting anyone is of test equipment and test personnel. I often get the answer to the tune of "We have our equipment calibrated every X months!" Great; good for you. But that has no bearing on knowing the gauge R&R of a piece of equipment and process which utilizes it. This is one of the largest, most misunderstood topics in testing; how trustworthy are your answers from the machine and people who use the equipment? Pretty much, without fail, most any lab doesn't spend any time finding out.


That's "science' for you. Folks always be in a hurry to get an answer, even if the answer ain't exactly right.

 

[SC Maintenance]

There was an interview with a Toyota design engineer - I thought I originally found it around here - that said Toyota had "proven" there was something like a 3% MPG increase going to 0W-16 vs 20 weight.

3% is a meaningless number to an individual, but to an OEM chasing CAFE credits - its a lot.

 

[4WD]

I could not agree more.

My experiences in working in quality labs and engineering development leads me to believe that most tests flat out ignore the topic of variation which in the real world. What happens with great frequency is that one or two lab tests are run and then they "model" the expected typical results using computer driven projections. While this is reasonably "good enough", it lacks validation many times.

Example:
I was asked to test two competing brand components for use in a cooling system. I was told to go run a couple back-to-back tests with each competing component. I did so, against my objections, and the results showed the two were "essentially equal" and management was happy. I asked the engineering management a few questions ...
- Hey guys, what's the gauge RnR on this test equipment? They had no clue.
- Hey guys, what's the variation of each single component in micro-analysis? They didn't know.
- Hey guys, what's the variation of each brand in macro-analysis? They didn't have an answer.
So they had no idea how accurate the test results were, how well any one specific component could produce the same result, and how likely it was that a production assembly system would produce the same result. They were just wanting to get some single-sample results and then model everything on computers after that.

One of my biggest pet-peeves is how trusting anyone is of test equipment and test personnel. I often get the answer to the tune of "We have our equipment calibrated every X months!" Great; good for you. But that has no bearing on knowing the gauge R&R of a piece of equipment and process which utilizes it. This is one of the largest, most misunderstood topics in testing; how trustworthy are your answers from the machine and people who use the equipment? Pretty much, without fail, most any lab doesn't spend any time finding out.


That's "science' for you. Folks always be in a hurry to get an answer, even if the answer ain't exactly right.

True - and far too many lack an actual repository of cause and effects connected to failures/rates - or even produced failure rates in service
No - It’s more related to their personal trauma data base
(remember a bad day) …

 

[4WD]

There was an interview with a Toyota design engineer - I thought I originally found it around here - that said Toyota had "proven" there was something like a 3% MPG increase going to 0W-16 vs 20 weight.

3% is a meaningless number to an individual, but to an OEM chasing CAFE credits - its a lot.

Well, yeah - there is CA in CAFE ...
But despite it all we had a surprising number of trucks, and SUV's, and Hell Cats ...

 

[SubieRubyRoo]

Well, yeah - there is CA in CAFE ...
But despite it all we had a surprising number of trucks, and SUV's, and Hell Cats ...

I am always amazed when I visit CA that regardless of all the official posturing and virtue signaling, that the actual people of CA give all of these things a great big middle finger. I see at least an equal amount of HellCats, ZL1s, Vettes, and other thirsty vehicles as I do Teslas, and I see more (per capita) solar panels on houses in the Midwest than in CA.

It takes me back to a root tenet of capitalism- people don’t give a flying flip if something is more virtuous if it’s not on the same price or cheaper as the other alternatives- nobody wants to pay $5/kWh for solar or wind when gas-fired electricity is 13 cents/kWh or nuclear is 5 cents/kWh. If there wasn’t interference, solar and wind wouldn’t be a thing til it was under 20 cents at a minimum!

 

[Al]

Obviously (I think...lol) there will be less wear with 5W-30 over 0W-20. But I have yet to see quantified numbers. No incentive to do it. Auto makers would NEVER publish it.

I remember an SAE paper-(I believe) that indicated the goal was to prove an engine could go 200,000 miles with thinner oil. It couldn't, so they lowered it...to what I don't recall.

 

[SubieRubyRoo]

Obviously (I think...lol) there will be less wear with 5W-30 over 0W-20. But I have yet to see quantified numbers. No incentive to do it. Auto makers would NEVER publish it.

I remember an SAE paper-(I believe) that indicated the goal was to prove an engine could go 200,000 miles with thinner oil. It couldn't, so they lowered it...to what I don't recall.

I think I remember what you’re talking about- and that it was lowered to 150k miles.