Bob I couldn't help but notice that you left my car out of your discussion. If you look at our database you will see that Toyota's EPA figures are inflated much higher than Honda's. The Insights (MT followed by the CVT at a distant second) and manual tranny Civic take the top 3 mpg spots. All the Honda's are getting very close to their EPA ratings. The Prius is not even close! Using EPA City (instead of a combined figure) is even more misleading.

According to EPA city the Prius2 gets 60mpg city but in real life the Prius2 only gets 47.5mpg combined from our database, a 26% exaggeration!

By comparison my car is rated 46mpg city but in real life gets 48.3 combined from our database, a full 5% more than EPA city.

The Prius is a fantastic car but it does not walk on water and it does not get 60 mpg in the hands of most drivers.

Hello,

This is just my opinion, but i strongly believe (before we start another endless discussion on which is the better hybrid system) that we should all leave the technicalities regarding the hybrid systems for toyota and honda to figure out.
The bottom line is, These two cars CAN EASILY do roughly 44 - 48MPG when driven correctly (if anyone is not even satisfied with those figures is beyond me) , therefore, if you're asking about the advantages regarding which has better mileage, the answer is , there is no advantage of getting one over the other.

Depending on how you drive, it will affect both cars anyway, therefore, I suggest that you seek out advantages and disadvantages about the two different car's other aspects instead, such as drivability, cargo space, interior room, feel, looks, price etc.
If you're planning to go buy either one, I suggest you take your time and choose the one that meets your lifestyle needs and suit your budget.
and that can only be achieved by having YOU physically going out and test driving both.

regards,
gj

Correct. In engineering, we like to keep as many items constant as possible and limit the variations to just one. I would have no problem with comparing the manual transmission Honda Civic to the two Honda CVT models:

City:
48 mpg - Civic I CVT
46 mpg - Civic I MT
49 mpg - Civic II CVT

Highway:
47 mpg - Civic I CVT
51 mpg - Civic I MT
51 mpg - Civic II CVT

When the Prius manual transmission comes out, I look forward to comparing it to the Civic manual transmission (don't hold your breath.)

The EPA figures comes from the exact same driving profile for each car. The GH database is useful for showing what a set of users are reporting and their differences with the EPA MPG simply restates the obvious . . . the EPA protocol needs to be updated. Until then, the EPA protocol is the only controlled, engineering reproducable data we have.

I guess I'm confused by your signature, "61.8". Did I miss something? How did you measure "48.3"? Is that from just the online display?

The reason I ask is the last two weeks and three fill-ups, my Prius I is showing a range of 52-80+ mpg on my daily commute and that includes 1 out of 10 miles at highway speeds. The weekly numbers are: 57.7, 63.9 and 54.2 mpg. My weekend, highway numbers are: 62.4, 54.3 and 50.5 mpg measured at the pump.

Here is my commute route. What is yours?

Good thing we don't use the combined MPG but just the City EPA number, right?

As for EPA numbers, I'm getting better than EPA with my NHW11, Prius I after my first 6 months, the winter months. I understand it may get better, we'll see. My combined MPG is coming in about 4.4% more than the EPA combined. But I notice you are #3 in the Honda Civic MT list and I'm only #5 in the Prius I list.

Bob Wilson

Operation Iraqi Oil Freedom:

Automatic, stock, project car.

My other 1500 cc car:

Automatic, stock, backup car.
Free speech, dialog and knowledge thrives without the poison of SPAM.

My personal lifetime display shows 63.9 mpg but I enter the mileage calculated at the pump so my sig shows 61.8 mpg from the pump figures.

48.3 is the average of ALL the HCH MTs in the database:

http://www.greenhybrid.com/compare/mileage/

47.5 is the average of all the Gen 2 Priuses in the database.

Excellent! I used the same methodology, the tripmeter divided by pump recept gallons. There has been some buzz in the Prius groups about using the online display MPG versus the calculated MPG. When the gas pumps use my online display to charge for gas, I'll switch camps but for now, I prefer manual calculations.

Ahhh, I see it now. The 47.5 is from the 'Prius II', the NHW20 models. I was confused and thought we might have been discussing user "City" mpg results. I've adopted a twice a week 'top off' to keep my City driving separate from my weekend Highway driving. I've also been paying more attention to the EPA City and Highway driving profiles:

http://www.fueleconomy.gov/feg/fe_test_schedules.shtml
As I have adopted EPA driving profiles, I'm starting to see simular and even better results from my NHW11 Prius I.

Bob Wilson

Operation Iraqi Oil Freedom:

Automatic, stock, project car.

My other 1500 cc car:

Automatic, stock, backup car.
Free speech, dialog and knowledge thrives without the poison of SPAM.

Hi David,
Not really. We did a poll of "Hybrid IQs" (use the search function to see the results.) We have a fairly normal distribution with a peak in the 141-150 range. With rare exception, folks in this range of IQs are good at focusing on the important things with the confidence of real world data to backup our opinions. Where we have facts and data, we tend not get 'wrapped around the axle' . . . unless, in my case, dealing with non-hybrid folks.

You wouldn't know of any non-hybrid folks in this thread, would you?

Bob Wilson

Operation Iraqi Oil Freedom:

Automatic, stock, project car.

My other 1500 cc car:

Automatic, stock, backup car.
Free speech, dialog and knowledge thrives without the poison of SPAM.

Honda Civic Hybrid does not have a "lean burn" engine. Honda Insight MT does.

Ken@Japan

Thanks Ken. I checked the Honda web site and I see the Honda has dual ignition yet shares variable valve timing and electronic control. I'll be more precise in the future.

Bob Wilson

Operation Iraqi Oil Freedom:

Automatic, stock, project car.

My other 1500 cc car:

Automatic, stock, backup car.
Free speech, dialog and knowledge thrives without the poison of SPAM.

I wish we had more than Honda's IMA and Toyota's HSD to discuss. GM has yet to introduce their two mode hybrid system. More systems is better - competition is good.

60.3mpg lifetime - 71mpg in winter months

Best Run >
www.cleanmpg.com

"fanatic" is what the lazy call the dedicated

Neither. The stop and go advanatage has to do with the fact that at slower speeds the engine doesn't need to spin over hardly at all, whereas it must run at idle most of the time in stop and go traffic in the case of the Honda. The Prius tranmission is basically a single fixed-gear ratio, which uses a differential to split engine power between the wheels, and a generator. When it needs more torque in lower gears, more of the power is diverted toward the generator, which then spins a second high-torque electric motor on the driven end of the transmission.

The drawback of the Toyota system is that at highway speeds, this method must be run in reverse, to "gear up" the car, meaning that the system continually wastes some energy at highway speeds by converting mechanical power to electrical power, then back.

The Honda system however uses normal geared (or belt-and-pulley) transmissions, so it wastes less engine power at highway speeds in the transmission. However, it wastes more at slower speeds.

The GM system sounds excellent on paper from an engineering perspective, and should feature the best of both worlds (between the Honda and Toyota Systems) whenever it's actually released. It has the power split feature of the Toyota system, which should make for good city mielage, but it can actually shift into a true high gear for highway cruising, meaning it should drastically cut down on elecrtic conversion losses. This will be combined with other fuel-saving systems such as cylinder reduction.