[Fat Charlie]

Welcome to this type of fun driving!

It's not so much that larger, more powerful engines can be more efficient, it's that larger, more powerful engines take less of a hit on efficiency when they enter inefficient conditions.

On level ground in a line of cars doing 65, my Fit can do over 50 mpg. Let all the other cars pull off and throw in a hill, I'm suddenly getting 25. Yes, my mileage was cut in half because my puny little 1.5 actually had to do some work on its own. But it's wrong to overlook the real numbers: my Fit at its worst is right at the Mustangs' averages and still beats the hell out of the F-150. What good is it to not drop all that much mpg on an uphill when the cost is bad overall mpg?

Let's turn it around: a big, strong engine gets overall what a puny Fit gets uphill. The underpowered car then increases its mpg the moment the hill slackens, and keeps getting higher mpg until the next hill. So while my little car's uphill mpg is pathetically below its average, it's average over 50k miles is 45 mpg.

I know, the (completely legitimate) response is... Fun. We're actually big fans of acceleration here, and pushing every part of the car's envelope- not a lot of granny drivers at this site. The biggest technique is Driving Without Brakes (DWB), but Pulse And Glide (P&G) is the first to start with. DWB's premise is that it's stupid to accelerate towards the stop sign, but carrying it much farther than that is not for the faint of heart. P&G's philosophy is that hard acceleration means less time spent burning gas and more time spent at cruising speed. I know where you're coming from- I was driving a Legacy GT, burning it up 40+ miles each way and getting 20-22 mpg doing it. Then I stumbled in here and did some reading. My next tank was over 28 mpg. I didn't leave earlier (daycare opens when it opens, you don't get points for being there early) and I didn't get to work later. Same Bat Times, same Bat Roads, more efficient methods of putting power to the pavement. In a car where a 400 mile tank was a myth, in the 92 tanks I logged since coming here my average tank distance was 449.8 miles.

But increase the power- you're right in wanting an engine that produces power more efficiently. You can even use it for tearing things up and get better mileage at the same time, or do one then the other. And have fun. Just know that it's you, not the car, that gets the mileage- but an engine that produces more power more efficiently lets you do all sorts of fun stuff!