Mobil 1 0W-16
- Thread starter cdavidc1949
- Start date
- Status
Originally Posted By: nap
Bwahahahaha... “3%-6% higher fuel economy during both hot and cold starts”. Yeah right because that’s how people use their engines most of the time
That's probably the diffetence in the instantaneous 250 ms power spike they saw that was mainly due to spinning up all the mass of the pump.
Bwahahahaha... “3%-6% higher fuel economy during both hot and cold starts”. Yeah right because that’s how people use their engines most of the time
That's probably the diffetence in the instantaneous 250 ms power spike they saw that was mainly due to spinning up all the mass of the pump.
Originally Posted By: nap
Bwahahahaha... “3%-6% higher fuel economy during both hot and cold starts”. Yeah right because that’s how people use their engines most of the time
Why do you need to be a total troll all the time? Your trolling has reached a ridiculous level.
They obviously mean during running with a cold engine and during running with a hot engine. Any person with reasonable intelligence would interpret that correctly. Anyone who interprets that as fuel savings during when cranking the engine is either a total troll or has serious issues.
Quote from the ASME article: "This combination significantly reduced the energy the pump consumed, resulting in a 3%-6% higher fuel economy during both hot and cold starts, with higher engine speeds producing greater fuel-economy benefits."
Bwahahahaha... “3%-6% higher fuel economy during both hot and cold starts”. Yeah right because that’s how people use their engines most of the time
Why do you need to be a total troll all the time? Your trolling has reached a ridiculous level.
They obviously mean during running with a cold engine and during running with a hot engine. Any person with reasonable intelligence would interpret that correctly. Anyone who interprets that as fuel savings during when cranking the engine is either a total troll or has serious issues.
Quote from the ASME article: "This combination significantly reduced the energy the pump consumed, resulting in a 3%-6% higher fuel economy during both hot and cold starts, with higher engine speeds producing greater fuel-economy benefits."
Originally Posted By: nap
Shannow I admire your patience. The only guy that I ever saw having more was a professional that used to be tutoring autistic kids.
Troll!!
Shannow I admire your patience. The only guy that I ever saw having more was a professional that used to be tutoring autistic kids.
Troll!!
Originally Posted By: ZeeOSix
Originally Posted By: nap
Bwahahahaha... “3%-6% higher fuel economy during both hot and cold starts”. Yeah right because that’s how people use their engines most of the time
That's probably the diffetence in the instantaneous 250 ms power spike they saw that was mainly due to spinning up all the mass of the pump.
I thought you were smart. You got fooled by a troll on a straightforward matter.
Originally Posted By: nap
Bwahahahaha... “3%-6% higher fuel economy during both hot and cold starts”. Yeah right because that’s how people use their engines most of the time
That's probably the diffetence in the instantaneous 250 ms power spike they saw that was mainly due to spinning up all the mass of the pump.
I thought you were smart. You got fooled by a troll on a straightforward matter.
Originally Posted By: Gokhan
Originally Posted By: ZeeOSix
Originally Posted By: nap
Bwahahahaha... “3%-6% higher fuel economy during both hot and cold starts”. Yeah right because that’s how people use their engines most of the time
That's probably the diffetence in the instantaneous 250 ms power spike they saw that was mainly due to spinning up all the mass of the pump.
I thought you were smart. You got fooled by a troll on a straightforward matter.
I wasn't "fooled" by his comment. My comment means there's more to the story of "3~6%" fuel savings than just from reducing steady state oil pump losses. Do the hydraulic pumping delta HP calculation with the numbers I gave earlier. Don't let the undies get too twisted up.
Originally Posted By: ZeeOSix
Originally Posted By: nap
Bwahahahaha... “3%-6% higher fuel economy during both hot and cold starts”. Yeah right because that’s how people use their engines most of the time
That's probably the diffetence in the instantaneous 250 ms power spike they saw that was mainly due to spinning up all the mass of the pump.
I thought you were smart. You got fooled by a troll on a straightforward matter.
I wasn't "fooled" by his comment. My comment means there's more to the story of "3~6%" fuel savings than just from reducing steady state oil pump losses. Do the hydraulic pumping delta HP calculation with the numbers I gave earlier. Don't let the undies get too twisted up.
Originally Posted By: Gokhan
Originally Posted By: ZeeOSix
Originally Posted By: nap
Bwahahahaha... “3%-6% higher fuel economy during both hot and cold starts”. Yeah right because that’s how people use their engines most of the time
That's probably the diffetence in the instantaneous 250 ms power spike they saw that was mainly due to spinning up all the mass of the pump.
I thought you were smart. You got fooled by a troll on a straightforward matter.
Here is the abstract of the original scientific study:
Investigation into the benefits of reduced oil flows in internal combustion engines (link)
Richard D Burke1, Chris J Brace1, Roland Stark2, Ian Pegg2
1Department of Mechanical Engineering, University of Bath, Bath, UK
2Dunton Technical Centre, Ford Motor Company, Basildon, UK
Corresponding Author: Richard D Burke, Department of Mechanical Engineering, University of Bath, Bath BA2 7AY, UK. Email: [email protected]
"The engine lubrication system is a vital element for engine health but causes a parasitic load on the engine which increases the fuel consumption: this load can be reduced by matching the oil flow to lubricating requirements using a variable displacement oil pump. In a first stage, two variable displacement oil pumps were installed on a 2.4-L diesel engine; experiments over the New European Drive cycle showed reductions in fuel consumption of up to 3.4% and up to 5.8% over the urban phase of the cycle. A variable displacement oil pump was subsequently installed on an instrumented engine capturing over 100 metal and fluid temperatures within the engine structure. This showed that reducing oil flows resulted in lower oil temperature by up to 4 °C during cold-start New European Drive cycle but hotter cylinder liner temperatures by up to 6 °C. The higher cylinder wall temperatures caused an increase of 3% in oxides of nitrogen emissions but a reduction of 3%−5% in carbon monoxide and hydrocarbon emissions. Finally, an energy flow analysis showed that the variable displacement oil pump can reduce oil pump energy consumption by 160 kJ (32%) but that this led to a 400-kJ reduction in friction and accessory work. These findings highlight the need for a system-level rather than a component-level approach to engine lubrication design to capture key thermal interactions."
Poster nap is a ridiculous troll. He needs to be banned from this forum. Ignorance is OK but he backs up his ignorance with constant name calling and insults. There is really no place for such trolling on this forum.
Originally Posted By: ZeeOSix
Originally Posted By: nap
Bwahahahaha... “3%-6% higher fuel economy during both hot and cold starts”. Yeah right because that’s how people use their engines most of the time
That's probably the diffetence in the instantaneous 250 ms power spike they saw that was mainly due to spinning up all the mass of the pump.
I thought you were smart. You got fooled by a troll on a straightforward matter.
Here is the abstract of the original scientific study:
Investigation into the benefits of reduced oil flows in internal combustion engines (link)
Richard D Burke1, Chris J Brace1, Roland Stark2, Ian Pegg2
1Department of Mechanical Engineering, University of Bath, Bath, UK
2Dunton Technical Centre, Ford Motor Company, Basildon, UK
Corresponding Author: Richard D Burke, Department of Mechanical Engineering, University of Bath, Bath BA2 7AY, UK. Email: [email protected]
"The engine lubrication system is a vital element for engine health but causes a parasitic load on the engine which increases the fuel consumption: this load can be reduced by matching the oil flow to lubricating requirements using a variable displacement oil pump. In a first stage, two variable displacement oil pumps were installed on a 2.4-L diesel engine; experiments over the New European Drive cycle showed reductions in fuel consumption of up to 3.4% and up to 5.8% over the urban phase of the cycle. A variable displacement oil pump was subsequently installed on an instrumented engine capturing over 100 metal and fluid temperatures within the engine structure. This showed that reducing oil flows resulted in lower oil temperature by up to 4 °C during cold-start New European Drive cycle but hotter cylinder liner temperatures by up to 6 °C. The higher cylinder wall temperatures caused an increase of 3% in oxides of nitrogen emissions but a reduction of 3%−5% in carbon monoxide and hydrocarbon emissions. Finally, an energy flow analysis showed that the variable displacement oil pump can reduce oil pump energy consumption by 160 kJ (32%) but that this led to a 400-kJ reduction in friction and accessory work. These findings highlight the need for a system-level rather than a component-level approach to engine lubrication design to capture key thermal interactions."
Poster nap is a ridiculous troll. He needs to be banned from this forum. Ignorance is OK but he backs up his ignorance with constant name calling and insults. There is really no place for such trolling on this forum.
Originally Posted By: Gokhan
Corresponding Author: Richard D Burke, Department of Mechanical Engineering.
Finally, an energy flow analysis showed that the variable displacement oil pump can reduce oil pump energy consumption by 160 kJ (32%) but that this led to a 400-kJ reduction in friction and accessory work. These findings highlight the need for a system-level rather than a component-level approach to engine lubrication design to capture key thermal interactions."
There's the rest of the story. There was also 400 kj of added energy savings due to other factors going on, which they probably rolled into the overall fuel savings numbers. Plus they don't say if that is kj per second, minute, hour or day - so can't really say what the watt or hp savings were. There's no way it's per second. Still missing pieces of the story.
Corresponding Author: Richard D Burke, Department of Mechanical Engineering.
Finally, an energy flow analysis showed that the variable displacement oil pump can reduce oil pump energy consumption by 160 kJ (32%) but that this led to a 400-kJ reduction in friction and accessory work. These findings highlight the need for a system-level rather than a component-level approach to engine lubrication design to capture key thermal interactions."
There's the rest of the story. There was also 400 kj of added energy savings due to other factors going on, which they probably rolled into the overall fuel savings numbers. Plus they don't say if that is kj per second, minute, hour or day - so can't really say what the watt or hp savings were. There's no way it's per second. Still missing pieces of the story.
Originally Posted By: ZeeOSix
Originally Posted By: Gokhan
Finally, an energy flow analysis showed that the variable displacement oil pump can reduce oil pump energy consumption by 160 kJ (32%) but that this led to a 400-kJ reduction in friction and accessory work. These findings highlight the need for a system-level rather than a component-level approach to engine lubrication design to capture key thermal interactions."
There's the rest of the story. There was also 400 kj of added energy savings due to other factors going on, which they probably rolled into the overall fuel savings numbers. Plus they don't say if that is kj per second, minute, hour or day - so can't really say what the watt or hp savings were. There's no way it's per second. Still missing pieces of the story.
OK, I'm glad that you are no longer talking about millisecond transient MPG gains during engine starts.
Yes, the reduced oil flow is leading to reduced friction losses not only in the lubrication circuit itself but throughout the engine. Also, this is the urban cycle (for which I estimated about 10 HP) and the effect would probably be smaller for highway driving. So, their numbers amplify Shannow's 100 W as 100W * [(160+460)/160] = 350 W. 5.8% saving would correspond to an engine output in the urban cycle of about 8 HP, with Shannow's 100 HP estimate. Given various uncertainties and lack of our access to the full PDF, the numbers are still in the ballpark.
Originally Posted By: Gokhan
Finally, an energy flow analysis showed that the variable displacement oil pump can reduce oil pump energy consumption by 160 kJ (32%) but that this led to a 400-kJ reduction in friction and accessory work. These findings highlight the need for a system-level rather than a component-level approach to engine lubrication design to capture key thermal interactions."
There's the rest of the story. There was also 400 kj of added energy savings due to other factors going on, which they probably rolled into the overall fuel savings numbers. Plus they don't say if that is kj per second, minute, hour or day - so can't really say what the watt or hp savings were. There's no way it's per second. Still missing pieces of the story.
OK, I'm glad that you are no longer talking about millisecond transient MPG gains during engine starts.
Yes, the reduced oil flow is leading to reduced friction losses not only in the lubrication circuit itself but throughout the engine. Also, this is the urban cycle (for which I estimated about 10 HP) and the effect would probably be smaller for highway driving. So, their numbers amplify Shannow's 100 W as 100W * [(160+460)/160] = 350 W. 5.8% saving would correspond to an engine output in the urban cycle of about 8 HP, with Shannow's 100 HP estimate. Given various uncertainties and lack of our access to the full PDF, the numbers are still in the ballpark.
Keep in mind that doing the same basic variable flow oil pump test on a small gasoline engine will most likely not give the same gains. Might want to find a good study on a gasoline engine to compare.
Shannow and I have discussed this topic before, and I don't recall seeing fuel saving claims that high. He might have sources to info he can link to.
Shannow and I have discussed this topic before, and I don't recall seeing fuel saving claims that high. He might have sources to info he can link to.
Originally Posted By: Shannow
Again, you are strawmanning me...building a strawman that I never said, and then defeating it.
Please stop...if you have issues with my statements, argue them...don't make stuff up, attribute it to me and argue that.
I just saw this. I'm sorry if I was offensive but then what you said often applies to how you respond to my posts as well.
My comment about viscosity was in response to your claim, "So to meet the demand at low speeds with thin oils, the pump has to be sized to deliver WAY too much at the top end," which I took an issue with, especially with the "WAY" part. My argument was that they really don't consider how much the bearing side leakage is more with thinner oil. They must design a system that will work at 100% leakage, regardless of the viscosity. That's because the side leakage is given by the Sommerfeld number, which can also change with RPM and load, regardless of the viscosity.
Again, you are strawmanning me...building a strawman that I never said, and then defeating it.
Please stop...if you have issues with my statements, argue them...don't make stuff up, attribute it to me and argue that.
I just saw this. I'm sorry if I was offensive but then what you said often applies to how you respond to my posts as well.
My comment about viscosity was in response to your claim, "So to meet the demand at low speeds with thin oils, the pump has to be sized to deliver WAY too much at the top end," which I took an issue with, especially with the "WAY" part. My argument was that they really don't consider how much the bearing side leakage is more with thinner oil. They must design a system that will work at 100% leakage, regardless of the viscosity. That's because the side leakage is given by the Sommerfeld number, which can also change with RPM and load, regardless of the viscosity.
Rather than being good and comprehensive, the article is two different issues...rolled into one paper.
Two issues that should not be combined, and the results therefore should not be used to inflate the "power losses" of a hydraulic pump as it has been used here...and then the extrapolation as to what my calculations lead to.
Thermal management of engine oil systems by controlling how and where oil gets circulated is a fundamental design issue. Work out how much you want where, and at what pressure...from that you size the pump to give what's required, plus an allowable margin.
Then pick the pump that matches the supply requirements, and if the pump can provide a flow/pressure curve that better matched the engine's requirement, then it reduces the wasted parasitic losses.
Putting a lower delivery pump on an already designed engine, and then claiming that the pump is responsible for delivering supplementary gains is poor science, and it's not automotive engineering by any stretch.
Engineering takes a bottom up approach to supply requirements, then sizes the pump to suit...
Two issues that should not be combined, and the results therefore should not be used to inflate the "power losses" of a hydraulic pump as it has been used here...and then the extrapolation as to what my calculations lead to.
Thermal management of engine oil systems by controlling how and where oil gets circulated is a fundamental design issue. Work out how much you want where, and at what pressure...from that you size the pump to give what's required, plus an allowable margin.
Then pick the pump that matches the supply requirements, and if the pump can provide a flow/pressure curve that better matched the engine's requirement, then it reduces the wasted parasitic losses.
Putting a lower delivery pump on an already designed engine, and then claiming that the pump is responsible for delivering supplementary gains is poor science, and it's not automotive engineering by any stretch.
Engineering takes a bottom up approach to supply requirements, then sizes the pump to suit...
Originally Posted By: Shannow
Rather than being good and comprehensive, the article is two different issues...rolled into one paper.
Two issues that should not be combined, and the results therefore should not be used to inflate the "power losses" of a hydraulic pump as it has been used here...and then the extrapolation as to what my calculations lead to.
Thermal management of engine oil systems by controlling how and where oil gets circulated is a fundamental design issue. Work out how much you want where, and at what pressure...from that you size the pump to give what's required, plus an allowable margin.
Then pick the pump that matches the supply requirements, and if the pump can provide a flow/pressure curve that better matched the engine's requirement, then it reduces the wasted parasitic losses.
Putting a lower delivery pump on an already designed engine, and then claiming that the pump is responsible for delivering supplementary gains is poor science, and it's not automotive engineering by any stretch.
Engineering takes a bottom up approach to supply requirements, then sizes the pump to suit...
You made it almost sound like the quantum measurement problem.
Rather than being good and comprehensive, the article is two different issues...rolled into one paper.
Two issues that should not be combined, and the results therefore should not be used to inflate the "power losses" of a hydraulic pump as it has been used here...and then the extrapolation as to what my calculations lead to.
Thermal management of engine oil systems by controlling how and where oil gets circulated is a fundamental design issue. Work out how much you want where, and at what pressure...from that you size the pump to give what's required, plus an allowable margin.
Then pick the pump that matches the supply requirements, and if the pump can provide a flow/pressure curve that better matched the engine's requirement, then it reduces the wasted parasitic losses.
Putting a lower delivery pump on an already designed engine, and then claiming that the pump is responsible for delivering supplementary gains is poor science, and it's not automotive engineering by any stretch.
Engineering takes a bottom up approach to supply requirements, then sizes the pump to suit...
You made it almost sound like the quantum measurement problem.
No, simple, logical system design...
Sorry, posting while you were editing it from the Heisenberg Uncertainty Principal to quantum measurement.
What would you do in your lab if a student started mixing conclusions from an ambiguous experiment ?
Drawing conclusions on a single variable, when the experiment itself doesn't control for the other things (like liner temperature in this one)...the Variance in NOx, HC, and CO point directly to their quantum of power "savings" being due to other then a pretty pump design.
Sorry, posting while you were editing it from the Heisenberg Uncertainty Principal to quantum measurement.
What would you do in your lab if a student started mixing conclusions from an ambiguous experiment ?
Drawing conclusions on a single variable, when the experiment itself doesn't control for the other things (like liner temperature in this one)...the Variance in NOx, HC, and CO point directly to their quantum of power "savings" being due to other then a pretty pump design.
Originally Posted By: Shannow
No, simple, logical system design...
Sorry, posting while you were editing it from the Heisenberg Uncertainty Principal to quantum measurement.
What would you do in your lab if a student started mixing conclusions from an ambiguous experiment ?
Drawing conclusions on a single variable, when the experiment itself doesn't control for the other things (like liner temperature in this one)...the Variance in NOx, HC, and CO point directly to their quantum of power "savings" being due to other then a pretty pump design.
They did their best. Yes, the increasing cylinder temperature increases the combustion efficiency, possibly evidenced by their emission numbers, even though the change was small. I would guess the effect was small, but yes, we don't know. These are researches from a major university and Ford Motor Co. simply doing their job. Before we judge the men, let's walk a mile in their shoes.
No, simple, logical system design...
Sorry, posting while you were editing it from the Heisenberg Uncertainty Principal to quantum measurement.
What would you do in your lab if a student started mixing conclusions from an ambiguous experiment ?
Drawing conclusions on a single variable, when the experiment itself doesn't control for the other things (like liner temperature in this one)...the Variance in NOx, HC, and CO point directly to their quantum of power "savings" being due to other then a pretty pump design.
They did their best. Yes, the increasing cylinder temperature increases the combustion efficiency, possibly evidenced by their emission numbers, even though the change was small. I would guess the effect was small, but yes, we don't know. These are researches from a major university and Ford Motor Co. simply doing their job. Before we judge the men, let's walk a mile in their shoes.
As an engineer, I was posting the appropriate mechanism for designing a lubrication system, and how to size the pump to supply the system that you have so designed.
The paper is retrofitting a variable displacement pump, and as it turns out of significantly reduced delivery, not just optimised delivery to an already operational engine design, and then in the first paper that you linked to claiming it was oil pump optimisation, and the second through changes in oil delivery and flow.
It's NOT a paper about the power savings of a variable displacement pump...regardless of shoe size.
Do modern research facilities give everyone a participation award these days for having a good honest crack at it ?
Must make them feel pretty good really.
The paper is retrofitting a variable displacement pump, and as it turns out of significantly reduced delivery, not just optimised delivery to an already operational engine design, and then in the first paper that you linked to claiming it was oil pump optimisation, and the second through changes in oil delivery and flow.
It's NOT a paper about the power savings of a variable displacement pump...regardless of shoe size.
Do modern research facilities give everyone a participation award these days for having a good honest crack at it ?
Must make them feel pretty good really.
OVERKILL
$100 Site Donor 2021
Originally Posted By: Gokhan
"The engine lubrication system is a vital element for engine health but causes a parasitic load on the engine which increases the fuel consumption: this load can be reduced by matching the oil flow to lubricating requirements using a variable displacement oil pump. In a first stage, two variable displacement oil pumps were installed on a 2.4-L diesel engine; experiments over the New European Drive cycle showed reductions in fuel consumption of up to 3.4% and up to 5.8% over the urban phase of the cycle. A variable displacement oil pump was subsequently installed on an instrumented engine capturing over 100 metal and fluid temperatures within the engine structure. This showed that reducing oil flows resulted in lower oil temperature by up to 4 °C during cold-start New European Drive cycle but hotter cylinder liner temperatures by up to 6 °C. The higher cylinder wall temperatures caused an increase of 3% in oxides of nitrogen emissions but a reduction of 3%−5% in carbon monoxide and hydrocarbon emissions. Finally, an energy flow analysis showed that the variable displacement oil pump can reduce oil pump energy consumption by 160 kJ (32%) but that this led to a 400-kJ reduction in friction and accessory work. These findings highlight the need for a system-level rather than a component-level approach to engine lubrication design to capture key thermal interactions."
ZeeOSix's point about this engine being diesel is also key to this discussion.
Regarding the bolded/underlined portion above, is there further clarification on this? Do they mean two, as in two different, at two different times, or two, as in replacing both the sump oil pump and potentially a HEUI pump?
"The engine lubrication system is a vital element for engine health but causes a parasitic load on the engine which increases the fuel consumption: this load can be reduced by matching the oil flow to lubricating requirements using a variable displacement oil pump. In a first stage, two variable displacement oil pumps were installed on a 2.4-L diesel engine; experiments over the New European Drive cycle showed reductions in fuel consumption of up to 3.4% and up to 5.8% over the urban phase of the cycle. A variable displacement oil pump was subsequently installed on an instrumented engine capturing over 100 metal and fluid temperatures within the engine structure. This showed that reducing oil flows resulted in lower oil temperature by up to 4 °C during cold-start New European Drive cycle but hotter cylinder liner temperatures by up to 6 °C. The higher cylinder wall temperatures caused an increase of 3% in oxides of nitrogen emissions but a reduction of 3%−5% in carbon monoxide and hydrocarbon emissions. Finally, an energy flow analysis showed that the variable displacement oil pump can reduce oil pump energy consumption by 160 kJ (32%) but that this led to a 400-kJ reduction in friction and accessory work. These findings highlight the need for a system-level rather than a component-level approach to engine lubrication design to capture key thermal interactions."
ZeeOSix's point about this engine being diesel is also key to this discussion.
Regarding the bolded/underlined portion above, is there further clarification on this? Do they mean two, as in two different, at two different times, or two, as in replacing both the sump oil pump and potentially a HEUI pump?
Originally Posted By: Gokhan
Originally Posted By: nap
Bwahahahaha... “3%-6% higher fuel economy during both hot and cold starts”. Yeah right because that’s how people use their engines most of the time
Why do you need to be a total troll all the time? Your trolling has reached a ridiculous level.
They obviously mean during running with a cold engine and during running with a hot engine. Any person with reasonable intelligence would interpret that correctly. Anyone who interprets that as fuel savings during when cranking the engine is either a total troll or has serious issues.
Quote from the ASME article: "This combination significantly reduced the energy the pump consumed, resulting in a 3%-6% higher fuel economy during both hot and cold starts, with higher engine speeds producing greater fuel-economy benefits."
Decency requires that, if you chose to quote the "high engine speeds" part, you also quote the drawbacks: "Reduced oil flow that improves fuel economy also increases combustion chamber temperatures and reduces piston cooling, which heats the metal cylinder liners by 2°C to 6°C. This effect reduced hydrocarbon and carbon dioxide emissions by 3%-5%, but also increased NOx by as much as 3%."
After VW's dieselgate, doing anything at the expense of increasing NOx is pretty much a no go for any sane manufacturer. This leaves you with just the potential "fuel economy during both hot and cold starts", as initially discussed.
The drawbacks with using high rpm are pretty much explaining why thin oil champion Honda is increasing the number of available AT speeds instead of using variable volume oil pumps. They just avoid "higher engine speeds" altogether, at which point the variable volume oil pump becomes as useful as a screen door on a submarine.
Originally Posted By: nap
Bwahahahaha... “3%-6% higher fuel economy during both hot and cold starts”. Yeah right because that’s how people use their engines most of the time
Why do you need to be a total troll all the time? Your trolling has reached a ridiculous level.
They obviously mean during running with a cold engine and during running with a hot engine. Any person with reasonable intelligence would interpret that correctly. Anyone who interprets that as fuel savings during when cranking the engine is either a total troll or has serious issues.
Quote from the ASME article: "This combination significantly reduced the energy the pump consumed, resulting in a 3%-6% higher fuel economy during both hot and cold starts, with higher engine speeds producing greater fuel-economy benefits."
Decency requires that, if you chose to quote the "high engine speeds" part, you also quote the drawbacks: "Reduced oil flow that improves fuel economy also increases combustion chamber temperatures and reduces piston cooling, which heats the metal cylinder liners by 2°C to 6°C. This effect reduced hydrocarbon and carbon dioxide emissions by 3%-5%, but also increased NOx by as much as 3%."
After VW's dieselgate, doing anything at the expense of increasing NOx is pretty much a no go for any sane manufacturer. This leaves you with just the potential "fuel economy during both hot and cold starts", as initially discussed.
The drawbacks with using high rpm are pretty much explaining why thin oil champion Honda is increasing the number of available AT speeds instead of using variable volume oil pumps. They just avoid "higher engine speeds" altogether, at which point the variable volume oil pump becomes as useful as a screen door on a submarine.
- Status
Similar threads
- Locked
