Hi All: Temps from 46 to 48 degrees F with winds calm on the multiple NB and SB runs. From the calibration drive, the aFCD offset "may" be 0.982 * indicated aFCD. SoC could not be deduced since there is no SoC display. As mentioned previously, the std. display does how kW consume from the ICE and the pack. During acceleration up to 65 and 70 mph, the ~ .5 miles to the reset launch point in both directions showed SoC. If I had a longer run up, I could have removed that SoC use but the exits on this stretch of I5 across Camp Pendleton would have incurred another 25-mile loop just to turn around, accelerate to speed, and reset at the exact elevation points on my test segment(s). 2020 Ford Escape Hybrid AWD Titanium Displays reset and "possibly" topped off. 46.3 mpg over 201.5 miles indicated, 205.6 miles on 4.518 gal = 45.5 mpg actual, 0.982* aFCD = Actual mpg. Just minutes before the Steady States data collection. With the Capless refueling not allowing a more accurate aFCD offset and this SoC use while accelerating to 65 and 70 mph before the actual measured runs, there are a number of inaccuracies that could have worked into the chart above. Using straight line analysis, the EPA highway (37 mpgUS) crossover occurred at 63.5 mph. I suspect the large 19s took the 2020 Ford Escape Hybrid to the woodshed vs the 17's on the Escape SE Sport Hybrid for example. The EPA highway for the Titanium trim (67.5 mph) occurs at 34.3 mph or a 34-mpg highway rating is what it should actually be rated at. Again, this result could be significantly higher - 1 to 2 mpg higher - as I know there was pack use during the 65 and 70 mph accelerations prior to the reset for the measured segment. Wayne
Hi All: From the 2019 Kia Niro EV Review, our first steady states data collection with an all-electric! 2019 Kia Niro EV Calibration Drive Reset to 6.1 miles/kWh over 12.1 miles indicated, 12.7 miles actual. Reset to 2.061 kWh with the Niro EV's battery from 98% to Full SoC. 12.7 miles on 2.061 kWh = 6.16 miles/kWh indicate a positive 0.9 percent aECD offset. 2019 Kia NIro EV Just moments before the Steady States last night. Temps from 49 to 51 degrees and calm winds for the NB and SB runs and 50, 55, 60, 65, and 70 mph indicated is actual per the Garmin. The 2019 Kia Niro EV Speed vs Energy Efficiency curve looks like this... The EPA highway rating of 3.03 miles/kWh was deduced from the Niro EVs 102 MPGe highway/33.7 kWh/gal. The EPA Highway efficiency crossover on a straight line estimate occurred at 73.0 mph indicating the 2019 Kia Niro EV is a bit more efficient than its 3.03 miles/kWh would indicate. I have found it is more efficient than its 3.65 miles/kWh rating around town as well. Wayne
Hi All: From the 2020 Toyota Prius AWD-e intro, first drive, and now review week (url=2019 Toyota Prius Gains Traction Just Weeks from Today), the steady state details follow. 2020 Toyota AWD-e Calibration Drive Initial topoff at a Shell in Torrance, CA with the aFCD, Trip A, and Garmin reset. Final topoff at a Shell in Carlsbad, CA. 81.6 mpg over 79.6 miles indicated, 81.4 miles on .988 gallons = 82.4 mpg actual. A suspect positive aFCD offset of 1.0098 or 1.01 was the result. I was actually surprised to see an aFCD positive offset on a Prius as our experience has shown only the topoff to topoff refuels in prototypes have provided a positive or neutral offset. When we get our hands on the consumer model(s), the offsets go negative up to a maximum of 9 percent as we experienced from an Eco trim during a triple digit result while driving from the IL/WI border to Detroit a few years back. While I have some confidence in the measured result, I went on to consume an entire tank and refuel just to make sure this was not an anomaly... 4-days later, I am sure glad I ran this tank down to come up with a more accurate aFCD offset and it is negative as expected. 2020 Toyota Prius AWD-e Final aFCD Calibration 66.5 mpg and 544.1 miles indicated - 556.4 miles actual on 8.932 gallons = 62.3 mpg. The aFCD offset is .937 or negative 6.3 percent. 2020 Toyota Prius AWD-e Just moments prior to Steady State data collection last night and into this morning. And the 2020 Toyota Prius AWD-e's Speed vs FE graph. Temps ranged from 52 to 55 degrees and winds were calm during the data collection. Indicated speed from the speedometer was 1 mph low of actual from 50 to 70 mph. Data was collected at 51, 56, 61, 676, and 71 mph indicated and 50, 55, 60, 65, and 70 mph actual. SoC changes were non-existent other than 1 bar loss at 70 mph on the NB run. It recovered within 100 yards of passing the flying data record point so there was a minimal effect. On a straight-line analysis, the EPA highway (48 mpg) crossover occurred at just 66.7 mph. While the 66.7 mph EPA highway crossover indicates the EPA highway estimate is fine but this result is the lowest crossover speed we have seen from any Toyota or Lexus to date. It was close and I suspect those optional 10-spoke chromed alloys our Prius AWD-e was equipped with were a factor in this somewhat low result. Wayne
Hi All: I completed the first measured fill with a quick 60-mile run down to the US/Mexico border to bring the Prius Prime down to low fuel. Like past Prius', the over report came to a staggering 8.1 percent. 2020 Toyota Prius Prime Limited First Measured Fill 640.3 miles on 9.413 gal = 68.0 mpg vs 74.0 mpg indicated. An 8.1 percent over report or aFCD*.919 = actual mpg. That is not a good result which means a double check with double up and pull another full tank measure. Except my week with the Prius Prime is coming to a close. I placed over 700-miles on the Prius Prime yesterday traveling from the US/Mexico Border all the way to the LA/Ventura County border and back while driving through the CBX, SAN, SNA, LGB, LAX, and BUR terminals to keep it real. This run also included two runs from sea level to almost 1,000' ASL on the CA-73 toll road, hours upon hours of LA, OC, and San Diego rush hour stop and crawl, and some spirited segments with one digit camped in the 8 range with the rest of the LA County crazies between rush hours on the 405 and 5. After running the tank down to Low Fuel for the second time on the same day, putting it all together looked like this... 2020 Toyota Prius Prime Limited Second and Accumulated Measured Fill 1306.9 miles on 19.368 gal = 67.5 mpg vs 73.3 mpg indicated. A 7.9 percent over report or aFCD* 0.921 = actual mpg. I really wish Toyota would stop doing this on some of their Prius'. If you notice the two fill results on measured fill #2, it was because I waited too long before another click and the pump shut down while I was taking a phone call between violently shaking the car and waiting for the fuel to settle. I restarted with another fill session and topped off with another 0.827 gallons for a total of 9.955 gallon on the second measured fill. Another disheartening indication is the actual miles traveled as measured by a Garmin is less than the Trip A/B/Odometer indicated by 0.4 percent. It was only a decade ago when Honda was sued for indicating 1.5 + percent optimistic Odometer results across much of their lineup. While .4 percent is minuscule, it only increases as the tires wear. I have not seen an odometer over report since a Jaguar Turbo Diesel we drive a few years back IIRC? The Speed vs FE of the 2020 Toyota Prius Prime PHEV-25 provided interesting results. 2020 Toyota Prius Prime Limited Just moments before Steady State data collection on Monday night/Tuesday morning. First off, the demarcation between a loss or gain in SOC is less than a mm thick so I am trying to estimate if there was any change during a given NB or SB run and incorporating it into the data’s results. Here is a pic of SoC indication while in Charge Sustaining mode during the AER test as posted above. 2020 Toyota Prius Prime Limited SoC indication during Charge Sustaining "Hybrid" mode Notice how small the demarcation is and how to judge a change of SoC from it is a guess at best? I was looking for the indication to be dead on with the eight of the blue to the single hash mark. I could control this during the run up to a given target speed by forcing an engine run to ring the bar level to the hash mark or allowing it to use EV to bring the level down to what I thought was even with the hash mark. During data collection, the 55 mph and 60 mph data had movement in one direction or the other so I am less confident in the output than I am with the 50 and 70 mph results. Even those could be skewed somewhat as Charge Sustaining mode with the Prius Prime only provides a total movement of about 3 to 4 mm below the hash mark and 1 mm above during your daily course of driving. Winds were calm and temps ranged from 53 to 55 degrees F. Winds were calm and temps ranged from 53 to 55 degrees F. Speedometer error was 2.0 mph low at 50, 55, and 60 mph, and 2.5 to 3.0 mph low at 65 and 70 mph. 2020 Toyota Prius Prime Limited Speed vs FE Using a straight-line analysis between 65 and 70 mph, the 2020 Prius Prime's EPA Highway (53 mpg) crossover occurred at 66.05 mph which is closer to our lower limit of 65 mph before calling a given EPA highway result cooked. Despite the colder temps, I did not incorporate a temperature offset. This Prius Prime Limited Trim came with the exposed multiple spoke windmill alloys which surely hurt the higher speed results by a few tenths. Wayne
The factory computer in my Versa over reports MPG consistently by 4-5MPG. I think manufacturers do this intentionally to make people unlike you and me who do their actual calculations think they're getting great mileage. It makes them think even though they're driving 90MPH on the highway they're still getting EPA estimated mileage, gives them a warm fuzzy feeling and gives them no reason to change their driving habits. Nearly every tank I run through the Versa the factory unit is reporting 50-53MPG yet my lifetime average is currently 47.005MPG. Best I remember when I bought the Versa the first tank the computer was reporting something between 46-46.5 MPG. When I did the actual calculations the mileage came to 42.345. It also seems the better my mileage the more the factory computer is off.
If you used 87 octane, 100% ethanol-free gasoline(E0), your paper & pencil MPG would probably be closer to your computer MPG.
That may be true but, E-0 is usually about $ .30-$ .40 a gallon higher here in town. I ran a few tanks of E-0 in one of my cars a few years ago and saw no noticeable improvement in MPG. Even if I could increase mileage by 10% the the cost is about 15-20% higher than E-10 so it doesn't make sense from a financial standpoint. Yes, it would make the numbers in the fuel log look good but, I'd rather not be paying an extra $3-5 per tank depending on difference in price per gallon at any particular time and how low I've ran the tank. If the difference was $ .10 a gallon I'd give it a try in this car.
First, the burning of 87 octane E0 does accurize the car's computer MPG reading, because 87 octane E0 is what is used to calibrate the car computer. The over-rated computer reading, while using poorly designated 87 octane E10 in an 87 octane designated gasoline engine, somewhat indicates the lack of performance of poorly designated 87 octane, 10% ethanol blends, used in 87 octane designated gasoline engines. Second, whether people don't like paying the gov't allowed pricing bias between E10 & E0, gasoline engines prefer E0 to E10. Over 15 years, my five 87 octane gasoline engines showed 8%, 8%, 7%-8%, 7%, & 5% increase in MPG, E0 over E10. Also detected, 87 octane gasoline engines run smoother. Also detected, 87 octane E0 has a trace extra very low rpm increase in torque. Again, ALL three characteristics indicate the preference of 87 octane engines for 87 octane E0. It is no mistake that auto engineers recommend 87 octane gasoline E0 for their vehicles. Third, poorly designated 87 octane E10 fuel blend is NOT 87 octane gasoline (E0). Poorly designated 87 octane E10 fuel blend is comprised of ten percent 114 octane ethanol AND ninety percent 84 octane gasoline. Neither of the components of poorly designated 87 octane E10 fuel blend are the designated 87 octane gasoline (E0) recommended by auto engineers.
I'm not denying that E-0 is a better grade of fuel whether it would or wouldn't help my mileage but, it's not worth the extra expense and extra out of the way driving to get it when there are at least 2 other stations I can think of with E-10 that are normally within 1 or 2 cents of one another on price and are the cheapest in town that I drive by on a regular basis. If one is cheaper than the other it will be Murphy's at Walmart which is where I buy most of my gas because it's handy to fill up there when we're there doing other shopping and is on the route to several other places we go on a regular basis. The other is a convenience store with top tier BP that's actually closer to my house if I need gas on short notice such as running out of lawn mower gas in the summer I and don't want to drive the 6 mile round trip to Walmart. Currently even a $ .30 increase in price in almost a 15% price increase and $ .40 is knocking on the door of 20% more expensive and when you start filling up 2-3 cars on a regular basis that runs into some money. The Versa only gets driven a small amount compared to one of the other cars and I still have to fill the Versa about every 2 weeks. I'm currently able to buy E-10 for $2.119 at a station I'm usually by several times a week. I haven't been by the station in town that sells E-0 for probably at least a month so I'm not sure what their price is now. That would be another disadvantage to me on using E-0 I'd be driving about 6 miles out of the way of my normal routes. It's also sold at a Southern States outlet and unless I'm mistaken they're only open 8AM-5PM M-F and 8AM-Noon on Saturday meaning I'd have to schedule when I could and couldn't buy gas. I have too many other things that have to be done on a specific schedule without including something as simple as filling my gas tank.
It is entirely plausible that the over report of the aFCD is tied to the E0 used in testing and published ratings. However, we should not confuse octane ratings with energy content. There's a magical relationship between the energy content shown above for E10 gasoline and E0 gasoline. 28.06 MJ/L divided by 29.0 MJ/L equals 0.968. Hmmm, that seems very close to the lower fuel economy that we're seeing compared to that reported by the aFCD. It's the energy content... I don't put too much weight on the "extra torque" at low RPM for E0 vs E10. I would be very surprised if one can actually feel the difference, but I'll accept that some people think they can. There's the other factor of different combustion timings possible (needs a smarter engine computer, e.g. Honda Civic) depending on fuel quality and octane. That may account for some of the perceived torque differences, probably real for the smarter engine and higher octane fuel. A bigger difference would be the advantage of coupling an electric motor with an ICE engine. i.e. hybrids ('engine' is a redundant term right, but it feels better putting it in) -- It makes no difference running on E10 gasoline other than the lower energy content. I'm with Ford Man. I wouldn't drive out of my way to buy E0, especially if the higher cost is not commensurate with the increased energy content. To me, it is a bit like comparing MPG for diesel versus gasoline cars. There's more energy content in the diesel fuel than gasoline, so you would expect higher MPG and it 'should' cost more, other factors being equal. A slight twist to the latter comparison is that the high compression diesel engine is inherently more efficient than lower compression spark engines so the MPG difference is a little more than accounted for by the energy content.
I guess I'm doing pretty good then getting 47MPG average with probably 10-20% city driving on E-10 if they do EPA testing on E-0 and only have a highway rating of 39MPG. Testing should be required to be on fuel that is readily available anywhere in the US not at select locations. There may be other stations and probably are with E-0 in this area but there are only 2 I know of within about 50 miles of my house.
I just checked puregas.org and found 11 places listed with 87 octane E-0 within 50 miles of my house. I don't call that readily available for the majority of consumers.
The first purpose of EPA testing was emissions. For accurate and repeatable results, the fuel blend needs to be a precise mix. The mix of consumer gasoline varies by petroleum stock and refinery, and that is before the addition of ethanol and other additives.
Of course, you deny. First, you only state that 87 octane E0 "is a better grade of fuel", which says nothing. What says something..... 87 octane ethanol-free gasoline E0 is the specific fuel that 87 octane gasoline engine engineers recommend to run best in 87 gasoline engines. Of course, you deny. Second, for the second time, you HAVE to repeat your contention that E0 "would or wouldn't help my mileage"..... Denial is easy when you "slick talk". You need to own your denial.
Why should I believe that? In a car that exaggerates mpg with E10, why wouldn't it exaggerate by the same factor with E0, if the car's method of sensing flow volume functions properly with either fuel? That should be independent of the well-known difference in energy content per unit volume.
You're right. Believing what many people have experienced, just can't be done..... specially if someone wants to believe the propaganda of "ethanol in gasoline industries".
Some cars are calibrated to be accurate, some are not. Wayne's tested some that are right on, some that are under, and many that report higher than reality. Mine, for example, reports 11% high. That's more error than just ethanol can explain. The next year model they changed the programming and it's more correct.
As I stated in another post I have used E-0 in other cars and saw NO MEASURABLE INCREASE IN MILEAGE. This wasn't simply on one tank of fuel but several consecutive tanks. I was also around and driving when they first began making E-10 back in the 1970's and didn't see any significant changes in the way my cars ran nor fuel mileage. I was only in my late teens in the late 1970's but even back then I checked fuel mileage from tank to tank. Of course back then the cars I was driving were only getting 13-15MPG so a small percentage would have been harder to trace. The last car I used E-0 in was an '88 Ford Escort that I consistently saw 40+MPG out of for over 500K miles and IT DID NOT SHOW ANY MEASURABLE INCREASE FROM PREVIOUS TANKS OF E-10. The reason I say E-0 is better fuel is because I have left E-0 in tanks long term with little effect but E-10 turns to a gummy varnish type mess.
The Sonic under reported with those conditions. The computer ignored any engine off miles for the calculation.
