So there was a discussion at work and it was said that the 5.4L F150s get better fuel economy than the 4.6L in a truck with identical equipment aside from engines. Similar remarks have been noted on the silverado line.
So I looked on the EPA fuel economy website and the 2008 f150 with the 4.2l V-6 and the 4.6L V-8 indeed get the same fuel mileage in testing, the 5.4 either gets slightly below or the same as the other two depending on trim package, which maybe has something to do with rear axle ratio or something.
I know there are many other examples of this across the automotive landscape.
I have always understood that engines are most efficient at low rpm and wide throttle openings. Now the econominder gauges you would sometimes see in the 1970s or 1980s, which was basically a glorified vacuum gauge would tell you otherwise.
Anyway it seems that its very simple, a gallon of gas has a certain amount of energy in it and it takes a certain amount of energy to move a vehicle that weighs xxxx.xx lbs down the road. This is assuming that the different engines have a similar volumetric efficiency.
Now take certain vehicles such as a 2008 V-6 Camry and it definitely swills more fuel than the I-4, these seem to be the anomalies though.
So why would a smaller engine not save fuel. That is my question.
So I looked on the EPA fuel economy website and the 2008 f150 with the 4.2l V-6 and the 4.6L V-8 indeed get the same fuel mileage in testing, the 5.4 either gets slightly below or the same as the other two depending on trim package, which maybe has something to do with rear axle ratio or something.
I know there are many other examples of this across the automotive landscape.
I have always understood that engines are most efficient at low rpm and wide throttle openings. Now the econominder gauges you would sometimes see in the 1970s or 1980s, which was basically a glorified vacuum gauge would tell you otherwise.
Anyway it seems that its very simple, a gallon of gas has a certain amount of energy in it and it takes a certain amount of energy to move a vehicle that weighs xxxx.xx lbs down the road. This is assuming that the different engines have a similar volumetric efficiency.
Now take certain vehicles such as a 2008 V-6 Camry and it definitely swills more fuel than the I-4, these seem to be the anomalies though.
So why would a smaller engine not save fuel. That is my question.