Not-so-hyper-miling (2020 Toyota Corolla 2.0L 6-speed manual)

[cRiPpLe_rOoStEr]

Originally Posted by #SaveTheManuals

Are MTs still generally popular in Brazil, like they are in Europe?

Nowadays mostly concentrated in the entry-level segment, even though some models are now featuring either a conventional automatic or an AMT as optional. MTs retain more popularity in Argentina than in Brazil.

I fear Toyota will sell so few MT models that they'll switch to CVT-only in short order.

It happened that way in Brazil...

[#SaveTheManuals]

I'm just going to use this thread as my MPG journal (unless someone points out that I missed a sub-forum area that would be more appropriate for this).

This weekend I filled up for the first time since I bought the car. I was unable able to reliably compute MPG since I don't know how full the dealer filled the tank. So the denominator is a little iffy. I also didn't count on not knowing the exact numerator in the equation; the car inconveniently reset the trip meter automatically when I filled up, and I didn't happen to look at the mileage beforehand.

Based on the ~30 miles that were on the car when we bought it, I can surmise that the MPG was about 36.33 -- but this figure isn't going into the books due to the unknown variables. The car's MPG computer said 37.2, so it's probably pretty close.

We needed to fill up because we had a ~130 mile trip into Boston this weekend. I'd say 75% of the mileage was fairly light freeway traffic (65 MPH posted), 20% was slow-and-go to stop-and-go highway traffic (~50 MPH posted), and 5% was typical stoplight-to-stoplight city driving with moderate traffic.

The car computer indicated 42.2 MPG for the entire trip. I'm pretty happy with that. The interesting part is that it was somewhat difficult to get the MPG significantly over 40 MPG on the freeway, but MPG soared in the slow-and-go ~50MPH segment. Other than the lower air drag at the slower speeds, I guess the traffic pattern approximated pulse-and-glide even if I didn't plan it that way.

[MetroMPG]

Originally Posted by #SaveTheManuals

I'm just going to use this thread as my MPG journal (unless someone points out that I missed a sub-forum area that would be more appropriate for this).

That's fine. I added your car info to the thread title for context. Consider starting a fuel log as well ... once you get a known good fill.


And I just thought of a question: are you driving the sedan or the hatchback?

surmise that the MPG was about 36.25 ... The car's MPG computer said 37.2

I'd be curious to know how far off it is. My experience with 2 newer cars (Nissan Micra and Mitsubishi Mirage, both automatics and manuals) is that they were fairly close (2-5% off), but still optimistic of course.

[#SaveTheManuals]

Originally Posted by MetroMPG

That's fine. I added your car info to the thread title for context. Consider starting a fuel log as well ... once you get a known good fill.

Thanks! I already added my car to the garage, and I'll start the fuel log once I have good data.

And I just thought of a question: are you driving the sedan or the hatchback?

Sedan. I preferred the hatchback, but the back-seat space wasn't going to work out well for us.

My experience with 2 newer cars (Nissan Micra and Mitsubishi Mirage, both automatics and manuals) is that they were fairly close (2-5% off), but still optimistic of course.

Hopefully it's close! With the imperfect data I have now, the computer is 2-3% optimistic. If that holds true with better data then I'll be pretty happy. The computer on my Odyssey seems to be around 5% optimistic, but on one long trip it was off by something like 12%! I just called that a mulligan and assumed the fuel pump must have shut off a little early on the previous fill.

[#SaveTheManuals]

I had occasion to fill up the tank for the 2nd time today. Trip computer indicated 41.0 MPG, and by my math it came out to 40.4866. The trip computer was about 1.3% optimistic. I'm not going to complain about that at all.

For more reliable calculations I'm letting the auto-filler handle shutoff when it wants to, then holding the handle on low until I see gas coming up to the opening of the tank. That way "full" means full. Hopefully that's not too full

Just as in life, the journey on this last tank of gas wasn't always ideal. In addition to the slow-and-go/stop-and-go trip to Boston I mentioned earlier, I had a string of bad luck in town today with traffic lights, pedestrians, large trucks pulling out in front of me, and rain (which seemed to have a large impact on the rolling resistance). Plus my wife put about 1/5 the miles on this tank, and who knows what's happening to the MPG when she drives. But we went from 36.xx to 40.5 between the 1st and 2nd tank, so I'm going to look on the bright side of life.

Plus, on the way home from the gas station I averaged a cool 45.3 MPG, which is 41% above the EPA rating of 32 MPG

[litesong]

Originally Posted by #SaveTheManuals

... a new 2020 Toyota Corolla 2.0L (6-speed manual).

The 2020 Elantras don't have manuals, anymore. Figuring the 2020 manual Corolla will sell enough manuals to make it worth the while, but the much lower selling manual Elantra, isn't economically viable. Our sub-$13,000 manual Elantra is wonderful.

[#SaveTheManuals]

...at least for a fairly short trip. Trip was 12.6 miles and the computer indicated 49.4 MPG. A few minutes earlier it was up around 51, but...pictures or it didn't happen.



The entire round trip was 26.3 miles, and the average for the whole trip was 47.1 MPG.

I'm starting to doubt my ability to properly exploit BSFC, because I achieved the 49.4 only using granny techniques. On the (slightly longer) return trip I averaged 45.0 while trying to use BSFC. There's only a ~30 foot elevation difference between the endpoints, so that shouldn't matter much.

[mpg_numbers_guy]

Great MPG!

Originally Posted by #SaveTheManuals

I'm starting to doubt my ability to properly exploit BSFC, because I achieved the 49.4 only using granny techniques. On the (slightly longer) return trip I averaged 45.0 while trying to use BSFC. There's only a ~30 foot elevation difference between the endpoints, so that shouldn't matter much.

Lowest RPM is usually better than BSFC for cruising. Lower RPM = higher engine load for a given speed = greater engine efficiency, usually more so than at peak BSFC. Cars are most efficient the closer they are to WOT (wide open throttle). Peak BSFC is for acceleration efficiency.

Peak BSFC is also for pulse-and-glide - accelerate at peak BSFC, and then engine off coast. Usually this technique is for the more extreme hypermilers; it got tiring very quickly when I did it in my Civic.

[#SaveTheManuals]

Originally Posted by mpg_numbers_guy

Lowest RPM is usually better than BSFC for cruising. Lower RPM = higher engine load for a given speed = greater engine efficiency, usually more so than at peak BSFC. Cars are most efficient the closer they are to WOT (wide open throttle). Peak BSFC is for acceleration efficiency.

I was attempting to exploit BSFC by accelerating fairly briskly (and shifting so I'm roughly in the 2,000-3,200 RPM range at all times), and then moving into my final gear for lowish-RPM cruising (roughly 1,500). I do OK this way, but seemingly not as good as just accelerating very slowly.

While accelerating granny-style causes a long, slow attenuation in the indicated average MPG, BSFC tanks it rather dramatically. Granted, after getting up to speed then I can spend more time at low-RPM cruising and make up a lot of the difference. But -- at least with the techniques I'm applying -- granny driving appears to be slightly more effective.

The BSFC concept makes sense to me, but where the rubber meets the road (ugh, sorry), I'm having trouble realizing the theoretical benefits. More than likely I need to adjust my technique a little...and it wouldn't hurt to get my hands on the actual BSFC maps for my engine as well as something like the ScanGauge to verify that I'm hitting the intended engine load.

[mpg_numbers_guy]

Yes, lowest RPM at wide open throttle is most efficient for acceleration too, but for most people that is just dogged slow, and only offers a slight efficiency advantage to peak BSFC acceleration. I tend to view the peak BSFC on my Insight (~2000 RPM) as the RPM I try not to exceed while accelerating. It's hard when the car has only 66 hp factory, but the mpgs are there. I surmise it would be the same with your Corolla, except that acceleration would be a bit faster due to your greater power. But for those who want to drive "normally" without nearly lugging the engine, peak BSFC is a pretty good compromise.

Peak BSFC also only works if you are at wide open throttle before enrichment. Usually this is around 75%-90% load, depending on the car. Anything past 90% and most cars start richening the fuel mixture, which reduces mpgs. A Scangauge is a great tool to have, but a bit pricey. The Torque Lite app (free) and a cheap bluetooth OBDII dongle ($10-$25) can show load and other parameters. The only downside to Torque is very inaccurate fuel economy readings compared to a Scangauge, but that doesn't matter since the Corolla already has fuel economy instrumentation.