I find the vacuum readings interesting. The lower reading to me would indicate the engine is working harder at the lower RPM. But the throttle I take it is relatively the same, going by the 24 & 23 readings. My gut feeling is the higher vacuum is the better mileage, but I cannot wrap my brain around the same throttle.
The trick question is how do you determine the sweet spot of an engine for fuel mileage, and for power. Some dynos will give the fuel consumption for the various RPM's at full throttle. But what if you only need the engine to produce 100HP to keep it rolling down the road? How do you come up with the best RPM, and decide gear choices.
Many vehicles will now give you MPG readings, but most are instantaneous readings, as in right now. Push the go pedal down a little harder, and the reading will drop. I drove one truck that would give you the average for the last 5 mins, or something. I found that more usefull, But I do not think it changed my over all driving habits. One could even argue that it was more of a distraction.
The gas engine Pacifica I had, would not use 8th and 9th, until after 75 MPH, except maybe for real light throttle, or even coasting down a hill. I could never get used to it shifting three times before I cleared an intersection. I had to kinda force myself to not try to feel the shifting, but I always ended up back there. I suppose in time I could have, but I got a great deal on the hybrid one.
Back to your question, I pick the 2450 RPM as the better mileage.
The trick question is how do you determine the sweet spot of an engine for fuel mileage, and for power. Some dynos will give the fuel consumption for the various RPM's at full throttle. But what if you only need the engine to produce 100HP to keep it rolling down the road? How do you come up with the best RPM, and decide gear choices.
Many vehicles will now give you MPG readings, but most are instantaneous readings, as in right now. Push the go pedal down a little harder, and the reading will drop. I drove one truck that would give you the average for the last 5 mins, or something. I found that more usefull, But I do not think it changed my over all driving habits. One could even argue that it was more of a distraction.
The gas engine Pacifica I had, would not use 8th and 9th, until after 75 MPH, except maybe for real light throttle, or even coasting down a hill. I could never get used to it shifting three times before I cleared an intersection. I had to kinda force myself to not try to feel the shifting, but I always ended up back there. I suppose in time I could have, but I got a great deal on the hybrid one.
Back to your question, I pick the 2450 RPM as the better mileage.
