Reducing Drag in an Engine

[Shel_B]

We're running thinner oils to reduce drag and increase mileage. Is there some way to measure and understand how much drag is reduced when going to thinner oil? I'm most interested in what happens when going from an HT/HS of 3.5 to something around 3.0, or from a Kinematic Viscosity @ 100 C of 12 to one of 10 or so.

 

[Bill_W]

We're running thinner oils to reduce drag and increase mileage. Is there some way to measure and understand how much drag is reduced when going to thinner oil? I'm most interested in what happens when going from an HT/HS of 3.5 to something around 3.0, or from a Kinematic Viscosity @ 100 C of 12 to one of 10 or so.

Dyno tests.

 

[Malo83]

Run 5w30 and you're doing all you can do, unless you buy some snake oil.

 

[skyactiv]

Run engines in a closed environment with a prescribed amount of fuel.

A possible example?

A Toyota engine under test load using 0W16 goes 36 minutes and 25 seconds while the same engine on 0W20 goes 36 minutes and 5 seconds on the same amount of fuel.

 

[Shel_B]

Run engines in a closed environment with a prescribed amount of fuel.

A possible example?

A Toyota engine under test load using 0W16 goes 36 minutes and 25 seconds while the same engine on 0W20 goes 36 minutes and 5 seconds on the same amount of fuel.

Are you saying that the reduced drag isn't able to be calculated, or that measuring fuel consumption is one way of determining a result? Is the example you've provided actual or hypothetical? I would imagine for a test such as you've described, certain parameters would have to be prescribed, such as engine, water, and oil temp.

 

[Bill_W]

Drag can also be measured by oil temperature.

 

[wpod]

You can motor the engine with an outside power source and measure the current use to spin the engine or use a torque measuring thingie which I can not recall the proper name at the moment. As well as on a dyno and measure the fuel consumption as certain engine loads. I am sure the major difference between the viscosities will be the power it takes the pump the oil. For Example when I had a boat I build a pre luber from a power steering pump I salvaged at work , There was a problem with the motor and the rental department said change the pump as well . So, I kept the pump any way during the summer I would use a drill motor to run the pump and with ease the drill would turn the pump and show 100 psi on the oil pressure gauge .with the same viscosity oil at 30*f the drill motor would start to smoke when turning the pump. I will ass the manufactures have changed the machining finishes. added coatings to the pistons and other parts . added roller rockers roller lifters etc to reduce friction. Our engine builders could probably tell us more on the subject

 

[Johnmpb]

Run some tests in your engine lab. Maybe even do a DOE

 

[Shel_B]

Drag can also be measured by oil temperature.

How, and how does the temp equate to real world numbers?

 

[Bill_W]

How, and how does the temp equate to real world numbers?

Are you asking about drag and then asking about real world quantifiable numbers. Rotating forces with oil film on each part that is stationary at the metal contact. Flow is in between. Does that mean temperature would be less, with less viscosity? Measure is different in every engine and every oil but higher viscosity equals more oil heat. The only thing you can quantify if you only change viscosity.

 

[High Performance Lubricants]

You can motor the engine with an outside power source and measure the current use to spin the engine or use a torque measuring thingie which I can not recall the proper name at the moment. As well as on a dyno and measure the fuel consumption as certain engine loads. I am sure the major difference between the viscosities will be the power it takes the pump the oil. For Example when I had a boat I build a pre luber from a power steering pump I salvaged at work , There was a problem with the motor and the rental department said change the pump as well . So, I kept the pump any way during the summer I would use a drill motor to run the pump and with ease the drill would turn the pump and show 100 psi on the oil pressure gauge .with the same viscosity oil at 30*f the drill motor would start to smoke when turning the pump. I will ass the manufactures have changed the machining finishes. added coatings to the pistons and other parts . added roller rockers roller lifters etc to reduce friction. Our engine builders could probably tell us more on the subject

You are talking about a spintron. Most commonly used for valve train development.

 

[Kjmack]

Run engines in a closed environment with a prescribed amount of fuel.

A possible example?

A Toyota engine under test load using 0W16 goes 36 minutes and 25 seconds while the same engine on 0W20 goes 36 minutes and 5 seconds on the same amount of fuel.

I want that improvement , screw the engine

 

[Chris142]

If you really want to reduce drag replace all sliding surfaces with bearings.

 

[BigCahuna]

I'm a bit confused. Is the point of this post to save gas, or reduce wear on the engine?.,,,

 

[simple_gifts]

The only drag is another discussion about thick vs thin. j/k.

 

[SugarMouth]

I went from 5w-30 to 0w-20 and my fuel mileage did not change even a tenth, I make the same drive daily. I'll be going back to 5w-30 once I run out of 20.

 

[Shel_B]

I'm a bit confused. Is the point of this post to save gas, or reduce wear on the engine?.,,,

Neither. I am just curious to know if there's a way to quantify the amount of drag reduction in an engine by reducing the viscosity or the HT/HS. For example, if I go from a 3.5 HT/HS to a 3.0 HT/HS, how much drag is reduced in the engine? I'm not sure if I can be any clearer as I'm asking from ignorance on the subject, and may not even be formulating the question in an ideal manner.

For example, if the HT/HS is reduced by 10%, from 3.5 to 3.1, will drag be reduced by 10%?

 

[PimTac]

My uneducated guess is that there might be a difference between running a 0w16 and a 15w40 or thicker oil but how to measure that is beyond my thinking. Difference between adjoining grades, probably not worth measuring.

 

[Johnmpb]

Neither. I am just curious to know if there's a way to quantify the amount of drag reduction in an engine by reducing the viscosity or the HT/HS. For example, if I go from a 3.5 HT/HS to a 3.0 HT/HS, how much drag is reduced in the engine? I'm not sure if I can be any clearer as I'm asking from ignorance on the subject, and may not even be formulating the question in an ideal manner.

For example, if the HT/HS is reduced by 10%, from 3.5 to 3.1, will drag be reduced by 10%?

Can you measure drag and does it matter?

 

[RDY4WAR]

Spintron!