2014 Mitsubishi Mirage vs. Geo Metro MPG -- fuel economy showdown
http://mirageforum.com/imgs/Mirage-v...ose-to-nos.jpg
Before the 2014 Mirage came along, the last time a 3-cylinder, 4-seat economy car was available in North America was back in 2000, when you could still get a General Motors/Suzuki love child known as the Geo/Chevrolet Metro.
The Metro was a basic little car that was cheap to buy and cheap to run (at or near the top of the MPG charts each year). GM sold hundreds of thousands of them (under various names) over 15+ years, and plenty are still on the road. Improbably, the little car even developed a cult following among efficiency enthusiasts that endures today.
Lately, more than a few parallels have been drawn by auto writers between the old Metro and the new Mirage. (I disagree with a lot of the comparisons, but that's another story.) The subject of this particular analysis is the big kahuna: fuel economy.
Can a 3-cylinder 2014 Mirage match the MPG of a 3-cylinder 1998 Metro in real world driving?
http://mirageforum.com/imgs/mirage-m...nt-3-4high.jpg
1998 Geo Metro (Pontiac Firefly) and 2014 Mitsubishi Mirage
The upstart(s)
In one corner we have a pair of brand new 2014 Mirages with the 1.2L 3-cylinder engine making 74 horsepower and 74 ft lbs of torque. One comes with a 5-speed manual transmission, and one with a CVT automatic, both generously provided by Donnelly Mitsubishi, in Ottawa, Ontario. (Yes, that's a shameless plug. Thanks again, Corey! Go see Corey and buy a car.)
The time machine
The defender is a 1998 1.0L, 5-speed Pontiac Firefly... wait, a what? Relax - it's a Pontiac-branded Metro clone that was sold in Canada. Exactly the same car as the Geo/Chevy (except "built for excitement!" obviously). The Metro/Firefly 1.0 was rated at 55 hp and 58 ft lbs of torque.
Let's be clear, this isn't a lopsided comparison of a clapped-out 15 year-old rattle trap against a brand new car. No, sir. This Metro clone is a time traveler from the past, with just 32,000 gentle highway kilometers under its belt line. (That's less than 20,000 well-maintained miles, for the Metrically challenged.) Not a typo. It's my personal car. I don't drive it an awful lot.
One slight wrinkle: the Firefly has been somewhat modified to get even better fuel economy than stock. (More on that below.) So the Mirage has a slightly tougher fight on its hands compared to a garden variety Metro of days gone past.
EPA ratings:
On paper, it looks like a fight that will be too close to call: The '98 1.0L 5-speed Metro had a combined rating identical to the 1.2L CVT Mirage.
Here's the full EPA menu:
The most interesting part of these ratings is the automatic transmissions.
- The Mirage's CVT is rated better than its manual transmission in both the city and highway tests.
- The Metro's automatic transmission wasn't worth diddly squat. Paired only with the 1.3L engine in '98, it was an agricultural era 3-speed slushbox with no lockup torque converter -- an outdated design that knocked fully 13 mpg off the 5-speed's combined rating!
The age of the manual transmission is long past in North America, and Mitsubishi knows the vast majority of Mirage buyers will go for the automatic. So, good for Mitsu for sticking some technology between the engine & wheels that doesn't penalize today's lazy-ass drivers to the same extent it used to.
Urban showdown - the route
The stage for this comparison is a 10.6 km (6.6 mile) residential/arterial route in a large city (Ottawa, Ontario). This is exactly the habitat these cars were meant for, and where most will be used.
http://mirageforum.com/forum/attachm...1&d=1382988516
View on Google Maps: http://goo.gl/maps/e5TLa
This is a combination of quiet residential and multi-lane arterial roads, with moderately busy traffic throughout (but no stop & crawl). Speed zones range from 40 through 70 km/h (25-43 mph).
Being mid-autumn, the weather is not ideal for showcasing maximum MPG. (The day of the test, it was a chilly 5C / 43F and windy. For full details on the route & weather conditions, see this thread.)
Driving style
Nothing fancy here. I use a smart, moderate driving strategy, a.k.a. "ecodriving". No hypermiling techniques like pulse & glide; no shutting the engine off while coasting; no sub-speed limit dawdling; no drafting (I never do this anyway). The engine remains on at all times, even at long stops.
The magic bullet for getting good city fuel economy is paying careful attention to what's happening down the road. I rarely burn fuel only to turn it into brake dust -- meaning, I avoid rushing into transitions (slowdowns, stops or turns) where I have to brake hard. In city driving, the brake pedal is your MPG enemy.
With the manual transmission, I accelerate moderately while keeping RPM low, shifting early and getting into the highest gear possible once at "cruising" speed. With the automatic, I ease up briefly on the throttle once at "cruising" speed to ensure the Mirage's 2-speed auxiliary CVT gearbox shifts into high gear.
Corey, the Mitsu sales rep who came along, will say about me: "he drives like a grandma."
But I keep up with traffic. The only times it appears I don't is (A) when starting up from a stop (I allow a larger gap to open in front of me than a typical driver); and (B) when I spot something like a traffic slowdown or fresh red light ahead (I ease off the gas early, while drivers ahead continue burning fuel all the way to the point where they stand on their brakes at the last minute).
I can forgive Corey's "grandma" comment -- this is a driving style that *feels* slow because it's smooth, not because it's actually slow. We cover the same distance in the same amount of time as the typical, brain-dead drivers around us.
http://mirageforum.com/imgs/metro-mirage-front.jpg
Instrumentation
The Metro/Firefly's results are taken from a ScanGauge-II fuel economy computer, calibrated to the car.
The Mirage comes from the factory with a resettable fuel economy gauge. There is of course the question of accuracy. A few early owners are saying the gauges are slightly under-reporting MPG. (Which, if true, will be a first in automotive history.)
Urban results
| Mirage 1.2L CVT automatic |
Mirage 1.2L 5-speed manual
|
Metro/Firefly 1.0L 5-speed manual
|
42 mpg (US)
5.6 L/100 km
17.9 km/L
50 mpg (Imp.)
14% above its 37 mpg EPA city rating |
48 mpg (US)
4.9 L/100 km
20.4 km/L
58 mpg (Imp.)
41% above its 34 mpg EPA city rating |
55 mpg (US)
4.3 L/100 km
23.4 km/L
66 mpg (Imp.)
53% above its 36 mpg EPA city rating |
The big takeaway here is that by using basic ecodriving techniques, each car beat its EPA city rating by a healthy margin.
The second thing that jumps out is how much better the manual transmissions performed relative to the CVT, despite the automatic's higher rating.
That result isn't surprising when you look at how he EPA rates cars with manual transmissions (using prescribed and decidedly non-eco shift points). It's not uncommon that an attentive driver with a manual transmission will outperform the same car with an automatic in city driving... even when the automatic has an equal or better EPA rating.
The Metro/Firefly advantage
So it would appear the Mirage can't touch a Metro in urban driving.
But remember, this Metro has been modified to get much better mileage than stock. Because of that, I'm not prepared to say that a factory 1998 Metro would get better real world city mileage than a new Mirage.
http://mirageforum.com/imgs/Metro-Mi...to-nose-sm.jpg
The Metro/Firefly differences / modifications ...
- Lighter weight: this is a big one. Not only is a stock Metro about ~100 lbs lighter than a manual Mirage, there was only one person on board vs. two people in the Mirage. So call it a ~300 lb advantage -- not insignificant in a city driving comparison.
- Reduced rolling resistance: the Metro's tires were inflated above the factory spec; the Mirage's tires were set at factory spec.
- Improved gearing: the Metro's transmission has been swapped out for one with a taller final drive ratio, giving it 20% lower RPM than stock (and lower than the Mirage)
- Engine modifications: an "efficiency" camshaft was installed that shifts the torque curve toward the lower end, to favour lower RPM operation; advanced timing.
- Aerodynamic modifications: aerodynamic drag isn't just a highway issue. Most vehicles burn half their fuel overcoming aero drag at speeds as low as 25-30 mph. To reduce drag, a number of aero mods have been fitted to the Metro/Firefly: partial grille block, smooth wheel covers; drag reducing "Kammback" (a much bigger version of the factory drag-reducing spoiler on the Mirage), and others.
Combined, these factors/modifications improve the Metro/Firefly's city mileage by 10-15% over stock.
So in reality, a Mirage 5-speed's mileage is on par with a factory '98 Metro 5-speed in urban use.
And it goes without saying that a head-to-head comparison isn't required to show that a CVT Mirage would simply spank an automatic Metro.
What about highway driving?
All three cars are within spitting distance of one another, but the Mirage CVT appears to have the edge on the open road. This makes sense since the CVT lets the engine run at lower RPM compared to the manual at cruising loads.
The Metro returns better mileage at lower speeds, but as speed increases, its fuel economy drops off noticeably faster than either Mirage.
http://mirageforum.com/imgs/graph-sp...rage-metro.jpg
Sources:
- Mirage manual: Speed vs. mileage/fuel economy chart - Mirage 1.2L 5-spd
- Mirage CVT: CleanMPG - Most Fuel Efficient Non-hybrid/Non-Diesel and its MT/AT Ratios
- Metro manual: Speed kills: testing MPH vs. MPG in top gear (This data was collected before the car was modified.)
It's worth noting: the comparison of these plots should be taken with a grain of salt.
It's difficult to compare numbers collected on different days, in different weather, on different routes. Despite driving on level roads and averaging results for both directions, there are a lot of variables at play, and I'm skeptical that the manual Mirage really comes out ahead of the CVT at 120 km/h / 75 mph. A valid test would be to have both cars go head to head, same day, same conditions.
The king is dead, long live the king!
If you've been waiting for a car company to produce an economy car with mileage that finally rivals the iconic Metro, your wait appears to be over.
Notably, the little Mitsubishi does it while offering 35% more power, way better crash protection, and a long list of standard and optional features that weren't even available in the old Metro. Most importantly, the majority of drivers who will choose the automatic CVT aren't penalized the way they once were. In fact, they will be rewarded during highway use.
The "cheap to buy, cheap to run" Metro did well for GM/Suzuki through the 80's & 90's. It'll be interesting to see how things go for Mitsubishi in today's much more competitive market.
http://mirageforum.com/imgs/mirage-metro-reflection.jpg
