City ecodriving comparison: 2014 Mirage CVT vs. Mirage 5-speed vs. 1998 Metro 5-speed

[Fat Charlie]

Cheap cars especially don't get the right maintenance. It seems that as long as they last until they're paid for, or until they can get rolled into the next car loan, it's good. Most people don't expect to run them for 100,000 or whatever the warranty is, they take that large number as a sign that it'll still be working and under warranty when they ditch it.

[MetroMPG]

Since I've been perusing the Metro/Firefly market for years, I can tell you that a lot of otherwise responsible elderly people buy entry level cars, and then hardly use them. (Unfortunately most -- but not all -- are automatics.)

The trick is finding a low miles one of those.

Originally Posted by dirtydave

They better take care of them!! I want a used one in a few years!!

Yup, me too.

[MetroMPG]

Dredging up this comment...

Originally Posted by niky

the upshift puts you just below the MIVEC changeover point

I was under the impression that the Mirage's MIVEC valve control was infinitely variable because it's not a cam profile swap system like the older MIVEC versions (= VTEC for Honda fans).

[MetroMPG]

A Mirage Forum member just did an 80 km / 50 mile comparison of a 5-speed car against the CVT, and unlike my test, his route was mostly highway - with the cruise set at 120 km/h / 70 mph.

The 5MT still edged out the CVT's mileage:

Route: highway (65%) and suburban driving (25%), with just a small portion in the city (10%). afterwards, i drove my mirage, which is a CVT. both were SE trim with climate control turned off. i did do the exact same route and made sure to do the same speeds at all points (whenever i was able). traffic was the same for both trips.

Results: the manual beat the CVT by about 2-3 mpg for the combined trip. i was surprised to find that it even beat the CVT on the highway. At 70 mph, the MT got 2 mpg better than the CVT.

for the entire trip:

• 5-speed: 47 mpg (US) / 5 L/100 km
• CVT: 45 mpg US / 5.2 L/100 km

MirageForum thread for more info: Mileage test between Mirage 5MT and CVT on set route (mostly highway) - MirageForum.com)

[Xist]

So, how to I respond to people telling me that the modern automatic is more efficient than manuals? "So is driving the speed limit, but you speed anyway, don't you?"

Oh, that does not sound helpful. So, "Only on the EPA test, not in actual driving?"

[Why am I supposed to put question marks not belonging to the quote inside of the quote when I am using a quote to make a question? I like being grammatically correct, but that does not make sense!]

[Hersbird]

I think what might happen in the EPA test is the acceleration is based on throttle position not a defined rate of acceleration. If they defined the rate of acceleration some cars may not even be able to achieve it. So in the EPA test the automatic is allowed to accelerate more moderately and shifted sooner. The manual is probably also required to be shifted at near it's red line, not short shifted like in this comparison. I also wonder in the EPA test if the manual ever even sees high gear.
car makers love this because it's a way to sell an expensive to buy and expensive to repair automatic.

[Fat Charlie]

It's not more efficient.

It's an appliance built to get better numbers than a manual transmission on a dyno while conducting the EPA test, and it does that.

FTL IRL, IMNSHO.

[niky]

Originally Posted by MetroMPG

Dredging up this comment...



I was under the impression that the Mirage's MIVEC valve control was infinitely variable because it's not a cam profile swap system like the older MIVEC versions (= VTEC for Honda fans).

From what I've seen, there's a dip in the torque curve and a slight bump where the valves switch to "high lift."

Seen here at around 4k - 4.5k rpm:



(yeah, it's all a bunch of wavy lines, but you really feel it when you're banging through the gears on the racetrack!).

If the mechanism had infinitely discrete changes, that burp shouldn't exist. You should be able to adjust lift incrementally so the torque curve is smoother.

Take note, this may not apply equally to US spec cars, since the calibrations are different. And yes, it could be due to other things... but if it looks, smells and feels like "VTEC YO"...

[oldtamiyaphile]

Originally Posted by Hersbird

I think what might happen in the EPA test is the acceleration is based on throttle position not a defined rate of acceleration. If they defined the rate of acceleration some cars may not even be able to achieve it. So in the EPA test the automatic is allowed to accelerate more moderately and shifted sooner.

As you can imagine, designing a test that fits all car/trans/engine combinations fairly is not possible.

For the NEDC tests, the cars is required to accelerate in X gear up to Y speed in Z time, slow to Q speed in R time and so on. The tests are done in at a fairly relaxed rate so even the slowest cars can complete them (especially since cars get faster every year and the tests are now quite old).

With an automatic, the test merely require accelerate to Y speed in Z time. The manufacturers can program the shift points as they like. This is why you see cars with robotised manual 'automatics' do better than full manuals that are otherwise identical -the only variable is shift points.

So yes, automatics are just another form of cycle beating.

[MetroMPG]

Originally Posted by oldtamiyaphile

For the NEDC tests, the cars is required to accelerate in X gear up to Y speed in Z time, slow to Q speed in R time and so on.

The EPA tests are the same; ie. acceleration is not based on throttle position, but following a speed vs. time trace on a computer screen connected to the dyno.