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After reading some posts about various hybrids having "sweet spot" speeds at which they get the best mileage, it struck me that the same might be true for my Accord. More importantly, it could be that the speeds I travel are not necessarily within those sweet spots. Since I began this journey I have made it a point to accelerate slowly up to the speed limit or under and hold steady until it's time to start slowing down for traffic, signals, or turns. But this hasn't worked very well in some cases.

A couple of weeks ago I fixed a "bug" in my load driving technique whereby I wasn't taking full advantage of downhill sections. Allowing the car to gain more momentum as I descend made it a lot easier to load drive up the next hill and realize a net gain in fuel efficiency. What I realized this morning is that a little extra speed helps my car on the flats, too. My usual 40mph is a struggle in the morning, and it's hard to cruise with FE above 30-33mpg while the engine is cold. It takes too much throttle to maintain speed. So this morning I tried cruising at 45mph instead. That worked much better! Instant FE readings were as high as 40mpg in the same locations where I was seeing 30mpg at 40mph. Even better, I didn't feel as though I was fighting the car to maintain speed. It makes driving much more satisfying! I ended up with an average of 30mpg over 5 miles, which isn't bad considering that my average is closer to 27 or 28mpg for that stretch. I'm pretty sure that this can be improved from 30mpg because I didn't adjust were I begin coasting. I generally ended up braking harder at signals and turns, meaning that I should have started coasting much earlier.

We'll see what happens tomorrow morning. I've never touched 31mpg heading in and it would be nice to bring the FE up another notch or two.

You probably popped into 5th gear? I don't know where your shift points are, but the 7the gen 5AT shifts at 42, and will hold 5th down to about 38. Lockup is at 48, and holds down to about 45.

4th is also an overdrive, but 5th is a very deep OD. The MPG difference for 40mph in 4th vs 5th is very noticeable. HAH specifics: IMA also gets wiggy near the shift point- probably a logic to disengage it as the transient occurs.

That comparison is 5th gear vs. 5th gear. When the engine is warm I can shift into 5th as low as 35mph and the engine is perfectly happy as long as there isn't much of an incline. What I'm finding, though, is that the engine isn't necessarily running efficiently at such low RPMs (1300-1600RPM). Fuel economy is better than the same speed in 4th gear but not as good as it could be if I just keep the high gear and cruise a little faster. 45mph seems to be ideal, presumably because combustion efficiency is fairly high but aerodynamic drag isn't ridiculous yet. I think that the effect is most noticeable in the morning because the extra fuel during warmup multiplies the effect.

gonavy, I believe brick is in a manual, not an auto.

Correct! Manual transmission.

ahh, yes. helps if I read the info in the upper corner. oops.