This Is What Mazda EPA MPG Results Will Look Like With Skyactiv-X HCCI Engines (Asterisk, Fine Print, Subject To Change)

Timothy Cain
by Timothy Cain
this is what mazda epa mpg results will look like with skyactiv x hcci engines

Mazda announced on August 8th what had long been rumored. The small Japanese automaker has successfully overcome the remaining issues which held at bay mass production of gasoline compression ignition.

Essentially, Mazda’s Skyactiv-X engines, due first in the next-generation 2019 Mazda 3, is intended to bring diesel-like ignition to small, supercharged four-cylinder engines, along with diesel-like fuel economy. However, the gas-fired Skyactiv-X engines will be wildly cleaner than diesel powerplants. Mazda has said in the past that these HCCI engines will likely limit the need for continuously variable transmissions. We also learned, with Mazda’s latest pronouncement, that the company’s Skyactiv-X engines will be significantly torquier than their Skyactiv-G predecessors.

If Mazda can live up to its pronouncements — the company says the engines are “still under development and figures are subject to change” — it’ll be a win for both the environment and driving enthusiasts. And because Mazda also claims a 20-30-percent improvement in fuel efficiency, it’ll be a win for your bank account, as well.

We wanted to see exactly where Mazda’s alleged fuel savings will put Mazda’s current products on the EPA’s miles per gallon scale, so here are the results of some quick math.

One column below shows the fuel economy ranges of Mazda’s current six-model U.S. lineup. We’ve opted to show the combined figures only to avoid cluttering with too great a quantity of numbers. Another column shows the same Mazda products with a 25-percent (the average of Mazda’s claims) reduction in fuel consumption. An extra column shows where current class leaders are positioned.

Naturally, rival automakers have just as much license as Mazda to make fuel efficiency advances over the next two or three years, so don’t assume the figures in the competitors’ column will hold through 2017.

Mazda2017 EPA MPG Range CombinedWith Skyactiv-X 25% Improvement (MPG) Class-Leading CompetitorMazda 328-3237-4337 *Mazda 628-3037-4052 **Mazda MX-5 Miata293930 †Mazda CX-329-3139-4231 ††Mazda CX-526-2735-3634 °Mazda CX-923-2431-3229 °°

* Presently, the Mazda 3 rival with the greatest combined mpg is the Chevrolet Cruze Diesel, rated at 37 miles per gallon combined. The Hyundai Elantra Eco has a combined rating of 35 mpg, as does the Honda Civic with a 1.5-liter turbo.

** The 2018 Toyota Camry Hybrid LE is rated at 52 miles per gallon combined. The most efficient non-hybrid midsize sedan is the base Camry at 34 miles per gallon.

† The Fiat 124 Spider, incidentally a Miata-based car, has an EPA combined rating of 30 mpg.

†† The front-wheel-drive Honda HR-V is rated at 31 mpg combined.

° The front-wheel-drive Nissan Rogue Hybrid is rated at 34 miles per gallon combined. Among non-hybrid compact crossovers, the FWD Honda CR-V 1.5T is the leader at 30 mpg.

°° The Toyota Highlander Hybrid is rated at 29 miles per gallon. The front-wheel-drive Kia Sorento 2.4 is rated at 24 mpg combined; the FWD non-hybrid Toyota Highlander at 23.

[Image: Mazda]

Timothy Cain is a contributing analyst at The Truth About Cars and and the founder and former editor of Follow on Twitter @timcaincars.

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  • Tstag Tstag on Aug 09, 2017

    It's pretty amazing how the worlds automakers continue to pour billions into ICE and gearbox development whilst knowing that the electric car is getting closer to the mainstream all the time. There must be a real opportunity for a company like Cosworth with a pure focus on engine development to step up and roll out new types of engine on an almost annual basis if the worlds automakers decided to centralise more investment with a company like them. Think of all of the recent advances we've seen from cylinder shut down capability to this. If a company like Cosworth focused on engine design it could outsource the part manufacturing to regional hubs and then get car companies to use existing facilities to do assembly. It's the way chip maker ARM operate so why not the car industry?

  • Luke42 Luke42 on Aug 10, 2017

    Mazda is still fighting the last war. Our next car purchase will be a Tesla Model 3, not a Mazda 3. Our Mazda 5 might last long enough to be replaced by a Tesla Model Y. If it doesn't last long enough, we will replace it with an Odyssey which had Honda Sensing. Honda has them beat as a value purchase, and also as a cheap cheerful car which handles well (especially in the Civic w/ Honda Sensing vs the 3). I want to root for Mazda, because our Mazda 5 is a 90s car done right. But Mazda's lineup is already obsolete, and it's going to be much more so driving assistance technology and electrification hit the mainstream when the Model 3 deliveries begin in earnest. Between the Model 3 and the Civic, I just don't see Mazda lasting in their niche -- unless their crossovers start to sell in extra-amazing numbers...

  • ToolGuy CXXVIII comments?!?
  • ToolGuy I did truck things with my truck this past week, twenty-odd miles from home (farther than usual). Recall that the interior bed space of my (modified) truck is 98" x 74". On the ride home yesterday the bed carried a 20 foot extension ladder (10 feet long, flagged 14 inches past the rear bumper), two other ladders, a smallish air compressor, a largish shop vac, three large bins, some materials, some scrap, and a slew of tool cases/bags. It was pretty full, is what I'm saying.The range of the Cybertruck would have been just fine. Nothing I carried had any substantial weight to it, in truck terms. The frunk would have been extremely useful (lock the tool cases there, out of the way of the Bed Stuff, away from prying eyes and grasping fingers -- you say I can charge my cordless tools there? bonus). Stainless steel plus no paint is a plus.Apparently the Cybertruck bed will be 78" long (but over 96" with the tailgate folded down) and 60-65" wide. And then Tesla promises "100 cubic feet of exterior, lockable storage — including the under-bed, frunk and sail pillars." Underbed storage requires the bed to be clear of other stuff, but bottom line everything would have fit, especially when we consider the second row of seats (tools and some materials out of the weather).Some days I was hauling mostly air on one leg of the trip. There were several store runs involved, some for 8-foot stock. One day I bummed a ride in a Roush Mustang. Three separate times other drivers tried to run into my truck (stainless steel panels, yes please). The fuel savings would be large enough for me to notice and to care.TL;DR: This truck would work for me, as a truck. Sample size = 1.
  • Art Vandelay Dodge should bring this back. They could sell it as the classic classic classic model
  • Surferjoe Still have a 2013 RDX, naturally aspirated V6, just can't get behind a 4 banger turbo.Also gloriously absent, ESS, lane departure warnings, etc.
  • ToolGuy Is it a genuine Top Hand? Oh, I forgot, I don't care. 🙂