MPG w/ Fat Tires and an ECU Tweak
Just thought I'd throw this out there.
I've modded the heck out of the suspension of this car. That doesn't affect fuel economy much, other than I can confidently take turns faster than I should with zero drama... thus slowing down less. The big killer for me is the 195/50 "max performance summer tires" that I have on the car (Dunlop Direzza ZIII), which are decidedly non eco-friendly.
My latest mod was an ECU tweak (add-on, OBD plug-in thingy) that has advanced ignition timing, and made the throttle a lot more sensitive. But, I don't think this has affected fuel economy at all... as long as I keep my foot out of it. Oh, and I'm also running 91 or 93 octane. Have been forever just in an effort to get the ECU to learn to keep the timing more advanced. And now that I've got a "tuner" that's forcing it to be more advanced, I "need" to run that octane.
So... Typical running around town, I'll see 32 mpg on short trips. Maybe 34-36 on a longer trip... maybe even 40-42 if it's a particularly long trip and I hit the lights just right. That's in "typical" suburban/urban traffic, driving "mostly economically", but not "hypermiling".
Decided to do a brief (maybe 10 miles?) post-lunch, casual economy run this afternoon. I reset the MPG with the car warmed up and while sitting at a light. I was pretty lucky with the traffic lights, and took a very light-traffic and low-speed route that kept me between 30 and 40 most of the time. I never turned off the AC, and never cut the engine. Neutral coasted for long flat or downhill stretches. DFCO when coming to a stop. Gentle/moderate acceleration. Shifted no higher than 3k and babied the throttle in top gear, never cruising below about 1800-2000.
Net result for this trip: 46.3 mpg.
Add 1.3% for tire size difference = 46.9 mpg
I'm still disappointed that it's SO HARD to get 50 mpg in this car without getting into serious hypermiling. (EOC, extreme coast-downs, etc) I could get my manual trans Yaris (with the same tire/wheel package) to 50+ with nothing but DFCO... perhaps not "easily", but "regularly". And the Versa that I used for a DE car with it's awful CVT... it would do 47-48 EASY, and hit 50+ on occasion if I used neutral coasting.
So... yeah, if I kept the stock narrow eco tires and ran without the AC... I'd probably hit 50-52 pretty easily. And that's good. But, for what this car is supposed to be, it seems that cars like the Yaris and Versa are capable of the same trick (50 mpg) without quite as much work.
I just have to remind myself that no matter how I drive my Mirage, I'm still getting AT LEAST 30% better fuel economy than the typical cars and SUV's around me.
One thing I will say about the Mirage is that it recovers its average MPG from a cold start better than anything else. The Yaris and Versa would make a cold-start trek from my driveway to the main road (25 mph, about 3/4 mile, two stops) and see maybe 12-14 mpg. The Mirage will regularly be at 21+ in that distance. Much better management of cold-start fuel. But, it loses HARD on acceleration. To get that little 1.2 to motivate, it uses some fuel.
My love/hate relationship with the Mirage continues.
But, it's still fun to show up at an autocross and beat 1/2 to 2/3 of everyone there in a car with 74 horsepower. (and get an easy 40+ mpg on the way home with delightful air conditioning and Bluetooth audio)
Speed kills mpg in any car.
Quote:
Originally Posted by
Eggman
The Mirage is often referred to as a City Car. It can work well on highways, but it's design tends to favor urban traffic.
Even the Toyota Prius does better in the city than the highway. Checking some Prius reviews, owners aren't getting much better than 50 mpg when their cars are pushed at higher speeds. The newer Prius seems to be doing better than the earlier models.
My 2017 Mirage ES (manual) always gets 40-50 mpg regardless of where I go. During the winter months, I would say it was doing around 40-44 mpg on average. This summer it seems to be doing about 5 mpg better than that overall. When I drove to North Dakota earlier this summer, I was doing 75-80 mph on the interstate with the A/C on. Under those conditions, it dropped to about 42-43 mpg. I don't remember fighting any strong winds on that trip, & that may have helped, too.
I just drive normal in my opinion. I keep my tires inflated to approximately 40-42 psi, but I do that with any vehicle I own (a few pounds under the maximum psi). I never look at the odometer for MPG readings, because I don't have much faith in them. I just use the calculator on my smart phone & do the math when I fill up each time. My Mirage turned over 15,000 miles this week, & I have never been under 40 mpg on any tank of gas. I live in rural southwest Wisconsin. I don't have to fight traffic much. Getting behind a school bus would be the extent of my frustration.
I took a trip to Lake Superior a couple weeks ago. That involved a different combination of highway driving (some 4-lane & 2-lane). I averaged about 46-48 mpg on that trip. That was with two people & a car full of luggage, coolers, & stuff.
Just looking at Toyota Prius as a comparison, the older models didn't do much better than my Mirage when driving at higher highway speeds. You could probably buy two discounted Mirages for the price of one Prius.
Speed is a killer for mpg on any car. That's why we had 55 mph speed limited implemented in 1974 (until 1995) after the great oil crisis of 1973. I think the Mirage is a nice package for the money. Creating a car that is affordable, reliable, and very economical is probably more of a challenge than creating an expensive vehicle of any sort. I really like the Mirage as is. If it was more like the Yaris or Fit, I would buy a Yaris or Fit. If Mitsubishi marketed the Mirage better (lowered the MSRP rather than their confusing gimmick discount deals), the value of the Mirage would be seen by more consumers/critics.