Calculate Efficiency with MPG and other things

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In summary, the conversation discusses the difficulty in deriving efficiency and power calculations for an engine based on its data plate. The individual is unsure if it is possible to calculate efficiency using only RPM, MPH, MPG, and BTU content, and suggests using truck weight and speed as additional variables. However, it is noted that engine efficiency and power can vary even at constant RPM due to throttle position. The only suggested method for accurately calculating this information is by putting the truck on a dyno and creating a performance map.
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My engine has a data plate stating it uses x amount of fuel to make x amount of power at x RPM. I can use that to derive the efficiency but then all other calculations I use, such as finding the HP at a given load using the fuel amount I get with MPG at a given speed, are all derived from that ONE efficiency. I know that is completely wrong but I have no other way to do it given the needed variables.

My question is, is it possible to derive an efficiency % using just RPM/MPH/MPG/BTU content...? I have a general idea of the truck weight (6500lb) but the more I think about it the more I think all you would need is BTU/MPG/and maybe speed. It seems energy used (in BTU content x gallons burned) to go a certain distance would tell you work done. But I have no clue. What do you guys think?
 
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This is very difficult. The engine efficiency and power depend on throttle position, so they can vary even at constant rpm. Putting the truck on a dyno and creating a performance map is the only way I can think of to do this.
 

1. How do I calculate fuel efficiency with MPG?

To calculate fuel efficiency, divide the distance traveled (in miles) by the amount of fuel consumed (in gallons). This will give you the miles per gallon (MPG) of your vehicle.

2. What is the difference between city and highway MPG?

City MPG refers to the fuel efficiency when driving in urban or stop-and-go traffic, while highway MPG refers to the efficiency when driving on a highway or at a consistent speed. Generally, highway MPG is higher than city MPG due to the reduced amount of stopping and starting.

3. How do I convert MPG to liters per 100 kilometers?

To convert MPG to liters per 100 kilometers, divide 235.21 by the MPG value. For example, if your car gets 30 MPG, the conversion would be 235.21 / 30 = 7.84 liters per 100 kilometers.

4. Can other factors affect fuel efficiency besides MPG?

Yes, other factors can affect fuel efficiency, such as driving habits, vehicle maintenance, and road conditions. Driving at a consistent speed, keeping your tires properly inflated, and avoiding excess weight in your vehicle can all improve fuel efficiency.

5. Is there a way to calculate fuel efficiency for electric or hybrid vehicles?

Yes, for electric vehicles, fuel efficiency can be calculated by dividing the distance traveled (in miles) by the amount of electricity consumed (in kilowatt-hours). For hybrid vehicles, the fuel efficiency can be calculated by combining the MPG for both gasoline and electricity usage.

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