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Mazda Claims 70 mpg For New Engine, No Hybrid Needed
thecarchik writes "There's no word on when the new version of the Mazda2 will finally reach the US but when it does we can reveal that it will return a fuel economy of 70 mpg — without the aid of any electric motors. This is because the car will feature Mazda's next-generation of drivetrain, body and chassis technologies, dubbed SKYACTIV. The new Mazda 2 will come powered by a SKYACTIV-G engine, Mazda's next-generation direct injection gasoline mill that achieves significantly improved fuel efficiency thanks to a high compression ratio of 14.0:1 (the world's highest for a production gasoline engine)." I wonder if a real-life-real-drivers 70 mpg car is what will actually arrive, or if such promises will dissolve like Chevy's promises about the Volt did.
WTF is this news?
VW Polo
70 miles per US gallon highway.
60 MPUSG combined.
50 MPUSG City.
Pre detonation doesn't matter. It's a direct injection engine. Fuel isn't injected until it's wanted, like diesels.
Normal gasoline engines have the air/fuel mixture inserted before the compression stroke.
I actually RTF(2nd)A, and it says:
"Mazda expects it to come in at 28 mpg city, 35 mpg highway with the five-speed manual, and 1 mpg less on highway mileage with the automatic."
Does not compute.
That's for the Mazda2 you can buy right now, not the one coming down the pipeline.
Not a typewriter
Maybe Chicago is an unusual case, but I don't recall seeing any gas stations where you can't buy diesel.
You are welcome on my lawn.
(1) Remember that diesel has about 1/3rd more BTUs per gallon than gasoline, so achieving 70mpg is no great feat. VW sold a Lupo that got 88mpg highway, and built a three-person family prototype that had 120 mpg.
(2) 70mpg is a challenge for gasoline, but it can be done. Suzuki and Honda have both made 70mpg engines, using 2 or 3 cylinders. My Insight averages almost 90mpg, even with the battery turned off. (The Insight SULEV has also been rated world's cleanest car by greenercars.org.)
"I disapprove of what you say, but I will defend to the death your right to say it." - historian Evelyn Beatrice Hall
The fact that modern vehicles often are in much worst shape after minor accidents is a trade off for the driver in them being in much better shape after major accidents. Many people with new vehicles will have full coverage and would rather their car be totaled in a fender bender than themselves be killed in a major accident.
1959 Chevrolet Bel Air and 2009 Chevrolet Malibu in 40 mph frontal offset crash test
Video
1959 Bel Air after crash
2009 Malibu after same crash
I realize that is a greater difference in years, and safety features, than you were specifically talking about, but the principle still stands.
Sorry to be a party pooper, but those numbers all stack up.
A US gallon is 83% of a UK gallon, so the the MPG figures are going to vary.
50 MPG (US) is roughly the same as 59 MPG (UK).
When using US gallons, its hardly surprising that you reach the US figure, rather than the UK figure.
Not everybody does things your way.
You just CONFIRMED what he said, not contradicted it. Diesel DOES have more energy per volume - more than 10% more.
I mean... yes, I read the numbers; I did post them after all. Still, it's the higher compression ratio that's the dominant factor, which is what my point had been.
Here, look at the 2010 Volkswagon Jetta. Here are the numbers for more-or-less identical vehicles, one with a diesel engine, one with a gasoline one (and a fairly high-compression one at that):
4 cyl, 2.0 L, Manual 6-spd, Diesel......41 mpg hwy
4 cyl, 2.0 L, Manual 6-spd, Premium.....31 mpg hwy
To drive one mile, it takes the gasoline-engined car 32% more fuel. By comparison, the diesel fuel itself has only 14% more energy per gallon. Energy density of the fuel alone is not sufficient to explain the difference. The difference comes from the efficiency of the engine.
I should note that this is in spite of the fact that the Otto cycle (which approximates gasoline engine operation) is more efficient than the Diesel cycle (which approximates the operation of real diesel engines) at the same compression ratio. Diesels, in practice, simply have compression ratios that are high enough to overwhelm that advantage.
Its one of their famous farming subsidies which keep farmers happy.
No, road diesel isn't taxed at a lower rate. You can get red diesel which has identical properties but has a red dye added (looks like snakebite and blackcurrant, hence the name "Diesel" for that drink) but which is taxed at a lower rate. You can't use red diesel in road vehicles.