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Originally Posted By: Cujet
due to better ring seal.
^^This
due to better ring seal.
^^This
Real Data: Oil Viscosity vs. MPG's
- Thread starter Phishin
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Originally Posted By: surfstar
At speeds of 95 mph, I wonder if that 5w30 was closer to a 20wt anyways?
On my previous car, I achieved my highest MPG on two tanks while running Pennzoil Conventional. Did I conclude that dino gave better MPG than synthetic?
No! One data point is not a valid comparison.
All we can take away from this thread is that that Accord achieved the observed MPG while running whatever oil was in it. We can't compare it to anything else. The title is very misleading and quite wrong.
Huh?
If you are implying that at 95mph the oil temps were elevated enough to thin the 30 grade oil enough that its equivalent to a 20 grade at lower temps then yes that's possible.
The more I test and compare the more I see the wisdom in shannow's posts.
He's been saying that the differences in the energy required when going from thicker to thinner oils is so negligible that turning the headlights off makes more of a difference(rough quote) I can honestly say that I think he's right.
There is no doubt that thicker oil is harder to pump and thereby consumes more energy to perform but as a driver its almost impossible to realize these potential gains. With traffic jams,red lights,wind rain and snow any potential savings gets lost in the noise.
Originally Posted By: Cujet
I tried both the Mobil 1 Advanced Fuel Economy oils 0w-20 and 0w30 in my 2.5L Jaguar X-Type w/manual transmission. I did not experience more MPG, or a better, free-er running engine. Overall, I'd say my experiment was a failure. As not only did my MPG or power not improve, but my oil consumption increased markedly.
However, this engine has adjustable cam timing, and the use of a slightly higher viscosity results in more accurate cam timing.
My engine clearly prefers 5W-40 and gets it's best MPG, about 27MPG, mixed driving with that oil. It's more responsive with more viscosity. Once again, possibly due to the cam phasers operating more accurately, and certainly due to better ring seal.
Very interesting theory. Most folks believe in order for the cam phasers to operate properly a thinner oil is required to flow though the small passages and to move the phaser accurately but your saying the opposite.
In my hemi with mds it uses oil as hydraulic fluid to close the valves in the deactivated cylinders. I've seen so many posts on the subject my brain hurts.
General concensus was that the system wouldn't operate properly if an oil thicker than 5w-20 is used.
I've observed that the system is actually smoother now as far as engagement and disengaging the system. And the engine almost feels like its pulling harder now.
In neutral with a 20 grade with a tap on the gas the engine revved up and the revs dropped very quickly. Now in neutral that same tap doesn't rev up as fast nor does it drop to idle as quickly however I'm not complaining. The engine is absolutely whisper quiet and feels better when I'm enjoying the acceleration with some heavy pedalling.
At speeds of 95 mph, I wonder if that 5w30 was closer to a 20wt anyways?
On my previous car, I achieved my highest MPG on two tanks while running Pennzoil Conventional. Did I conclude that dino gave better MPG than synthetic?
No! One data point is not a valid comparison.
All we can take away from this thread is that that Accord achieved the observed MPG while running whatever oil was in it. We can't compare it to anything else. The title is very misleading and quite wrong.
Huh?
If you are implying that at 95mph the oil temps were elevated enough to thin the 30 grade oil enough that its equivalent to a 20 grade at lower temps then yes that's possible.
The more I test and compare the more I see the wisdom in shannow's posts.
He's been saying that the differences in the energy required when going from thicker to thinner oils is so negligible that turning the headlights off makes more of a difference(rough quote) I can honestly say that I think he's right.
There is no doubt that thicker oil is harder to pump and thereby consumes more energy to perform but as a driver its almost impossible to realize these potential gains. With traffic jams,red lights,wind rain and snow any potential savings gets lost in the noise.
Originally Posted By: Cujet
I tried both the Mobil 1 Advanced Fuel Economy oils 0w-20 and 0w30 in my 2.5L Jaguar X-Type w/manual transmission. I did not experience more MPG, or a better, free-er running engine. Overall, I'd say my experiment was a failure. As not only did my MPG or power not improve, but my oil consumption increased markedly.
However, this engine has adjustable cam timing, and the use of a slightly higher viscosity results in more accurate cam timing.
My engine clearly prefers 5W-40 and gets it's best MPG, about 27MPG, mixed driving with that oil. It's more responsive with more viscosity. Once again, possibly due to the cam phasers operating more accurately, and certainly due to better ring seal.
Very interesting theory. Most folks believe in order for the cam phasers to operate properly a thinner oil is required to flow though the small passages and to move the phaser accurately but your saying the opposite.
In my hemi with mds it uses oil as hydraulic fluid to close the valves in the deactivated cylinders. I've seen so many posts on the subject my brain hurts.
General concensus was that the system wouldn't operate properly if an oil thicker than 5w-20 is used.
I've observed that the system is actually smoother now as far as engagement and disengaging the system. And the engine almost feels like its pulling harder now.
In neutral with a 20 grade with a tap on the gas the engine revved up and the revs dropped very quickly. Now in neutral that same tap doesn't rev up as fast nor does it drop to idle as quickly however I'm not complaining. The engine is absolutely whisper quiet and feels better when I'm enjoying the acceleration with some heavy pedalling.
Yes, I was saying that at higher oil temps that 30wt might have thinned closer to a 20wt. So basically (THEORIZING) 30wt @ 95 mph could equal a 20wt @ 65 mph. Just another reason I thought this thread didn't make sense.
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