Synthetic or "dino" oil?

[NORTY]

Back in 1994, during the Charlotte 600 NASCAR race, an oil company did a test with 2 Hendrick/Joe Gibbs car engines. Both were run the full 600 miles at race speed. Both were totally torndown post race. (They always are.) One was run with a synthetic oil and the other got "dino" oil. Both oils were the same viscosity (15W-40.) both engines were evaluated for everything including temperature (piston crowns were 600F for one oil and 616F for the other.)
Here is a pic of the pistons.
You tell me which piston was run with which oil...

[NORTY]

Here's a side view of the skirts of the same pistons.

[Vettehead Mikey]

I'll keep that in mind next time I'm running a 600 mile Nascar race.

Thanks.

[Derek]

And the answer is ??

[Vettehead Mikey]

I wish it was that simple. Running one engine type for 600 miles non stop at full throttle does not equate to the duty cycle of 12K miles on a completely different engine type used as a daily driver on the street. The street driven car would hopefully have had multiple oil changes for one thing and would never reach the same temperature extremes for extended periods as the race engine.

Yes, the photos due infer that synthetics do offer less tendency to accumulate coke deposits (their #1 reason for being developed for gas turbines) but is that really an issue on street driven Corvettes?

During my working career we ran countless development block tests with the engine family I was responsible for. These involved running the engine at full power on a dyno for 150 hours non stop or sometimes to destruction. Although the results very valuable in their own right, there was rarely equation with real world daily service over a period of months or years.

[Hib Halverson]

(snip)

Yes, the photos due infer that synthetics do offer less tendency to accumulate coke deposits (their #1 reason for being developed for gas turbines) but is that really an issue on street driven Corvettes?

(snip)

That GM has required synthetic engine oil in every Corvette built since 1992 seems to support the idea that it IS an issue in street-driven Corvettes.

[NORTY]

I posted this little exercise to illustrate the importance of the additive package used in oils...regardless of basestock origin.

The answer is....

The pistons on the left were run with SYNTHETIC oil.

The pistons on the right were run with "dino" oil.


Through the use of a Rockwell hardness scale, the engine temperatures were (measured post race @ the top ring land):
616F for the synthetic oil car.
600F for the "dino" based oil car.


Granted, this was done in 1994, and that is a century in oil development, but it's an accurate representation of how important an additive package is in the general performance of an oil.

[sstearns2]

What about the wear surfaces like bearings, cam lobes, lifters, etc?

Scott

[NORTY]

What about the wear surfaces like bearings, cam lobes, lifters, etc?

Scott

Unfortunately, I do not have pics other than the 2 views of the pistons.


* I also have pics of pistons from Archer Bros. cars in TRANS-AM racing. They pretty much show the same story.

[catbert]

Granted, this was done in 1994, and that is a century in oil development, but it's an accurate representation of how important an additive package is in the general performance of an oil.

...an important disclosure as current oils probably don't resemble oils of that era. That was several "specs" ago, and God knows the current state of the art.

[Vettehead Mikey]

I posted this little exercise to illustrate the importance of the additive package used in oils...regardless of basestock origin.

The answer is....

The pistons on the left were run with SYNTHETIC oil.

The pistons on the right were run with "dino" oil.


Through the use of a Rockwell hardness scale, the engine temperatures were (measured post race @ the top ring land):
616F for the synthetic oil car.
600F for the "dino" based oil car.


Granted, this was done in 1994, and that is a century in oil development, but it's an accurate representation of how important an additive package is in the general performance of an oil.

You sure you got your lefts and rights, right? The piston with the heavy coking is on the left, and that ran with synthetic?

[65TripleBlack]

I posted this little exercise to illustrate the importance of the additive package used in oils...regardless of basestock origin.

The answer is....

The pistons on the left were run with SYNTHETIC oil.

The pistons on the right were run with "dino" oil.


Through the use of a Rockwell hardness scale, the engine temperatures were (measured post race @ the top ring land):
616F for the synthetic oil car.
600F for the "dino" based oil car.


Granted, this was done in 1994, and that is a century in oil development, but it's an accurate representation of how important an additive package is in the general performance of an oil.

OK, "Curve Ball"...........I'll bite.
Dispersants?
Detergents?
Tell us the difference in the additive package which allowed such a dramatic difference DESPITE the syn oil's greater resistance to oxidation.
What was the oil temp that these engines were run at, and where was it measured?
And this proves what, about synthetic base stock as opposed to mineral?

[killain]

I have at times been invloved in a 'heated' debate over the use of Mobil-1 synthetic 5W/30 verses Amsoil 5W/30, and or say Castrol 'Edge synthetic 5W/30. Amost everyone say the Mobil-1 is an inferior motor oil compared to Amsoil or Castrol "Edge" ( The oil that has the scotmen running around wiping people with a dipstick, saying "Think with your dipstick Jimmy "

When I mention the Mobil-1, is the factory fill for all corvettes, Cadillac's, all Porsches, They use 5W/30 for the 300HP and below engines, and 0W/40 for all the super high horsepower engines, and then there is Mercedes-Benz AMG (the high performance division) and about fifteen other high performance auto manufactures. But I am alway told that it's a marketing ploy by Mobil. Which to me is as solid BS as it gets. I can't even imagine those Anal Prosche engineers putting anything in their prized powerplants, much less an American oil company.

But no matter what i suggest, people always want to believe that the big bad Mobil holds all the cards in marketing and that in reality is a flawed Motor oil and that they use a lesser grade basestocks Group 3 rather than Group 4, and that all the data is out and proved by a website, get this, www.bobtheoilguy.com and when I suggest that the engineers at GM really spent a lot of energy and thought process in picking Mobil-1, but I'm ridiculed as a dumba$%% who believes everything printed.

IAt this point I'm thinking all about the "Conspiract Theories" folllowing the assassination of JFK. Only this one is transfered to Motor oil. I never win, It's crazy !

[LLC5]

I have at times been invloved in a 'heated' debate over the use of Mobil-1 synthetic 5W/30 verses Amsoil 5W/30, and or say Castrol 'Edge synthetic 5W/30. Amost everyone say the Mobil-1 is an inferior motor oil compared to Amsoil or Castrol "Edge" ( The oil that has the scotmen running around wiping people with a dipstick, saying "Think with your dipstick Jimmy "

When I mention the Mobil-1, is the factory fill for all corvettes, Cadillac's, all Porsches, They use 5W/30 for the 300HP and below engines, and 0W/40 for all the super high horsepower engines, and then there is Mercedes-Benz AMG (the high performance division) and about fifteen other high performance auto manufactures. But I am alway told that it's a marketing ploy by Mobil. Which to me is as solid BS as it gets. I can't even imagine those Anal Prosche engineers putting anything in their prized powerplants, much less an American oil company.

But no matter what i suggest, people always want to believe that the big bad Mobil holds all the cards in marketing and that in reality is a flawed Motor oil and that they use a lesser grade basestocks Group 3 rather than Group 4, and that all the data is out and proved by a website, get this, www.bobtheoilguy.com and when I suggest that the engineers at GM really spent a lot of energy and thought process in picking Mobil-1, but I'm ridiculed as a dumba$%% who believes everything printed.

IAt this point I'm thinking all about the "Conspiract Theories" folllowing the assassination of JFK. Only this one is transfered to Motor oil. I never win, It's crazy !

That website "bobtheoilguy" has always amused me. "Internet engineering" at it's finest. Truth is Mobil 1 is one of the best oils you can put in your newer vette, has proven itself for decades, and when bought properly (walmart, etc), is definatley a bargain. You say that you never win, but I think you have proven that you already have!

[NORTY]

You sure you got your lefts and rights, right? The piston with the heavy coking is on the left, and that ran with synthetic?

Yes, the syntheitic oil varnished the underside of the pistons terribly. This could have gone the other way if the syn oil had a better additive package.