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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.
Normally high compression engines require high octane fuel, which costs more to produce. In the past they used to add a lead compound to (cheaply) improve the octane rating. Won't be allowed to do that these days...
It might get more MPG, but if the fuel costs more than teice as much per gallon you aren't going to save $$$
WTF is this news?
VW Polo
70 miles per US gallon highway.
60 MPUSG combined.
50 MPUSG City.
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.
Diesel contains significantly more energy per gallon than gasoline, so "MPG" comparisons to gasoline vehicles are totally useless.
Also, the UK fuel economy ratings are hopelessly optimistic, as are the Japanese tests.
The Third-Generation (ZVW30) Prius gets 59 MPUSG combined according to the UK tests, but 50 MPGUS according to the US tests. Anyone who actually drives their vehicle normally will tell you that the US tests are a lot closer to reality.
Whenever someone announces that a vehicle "beats" the Prius (or other hybrids) in fuel economy without a hybrid system, you have to look for one of several mistakes:
- Are they comparing diesel MPG (or L/100km) to gasoline? You can't do this because diesel contains more energy per unit volume.
- Are they comparing a small vehicle to a much larger hybrid? Yes, you can get good fuel economy in a Smart, but it also doesn't hold 4 people and is considerably less safe if you get in an accident with a larger vehicle.
- Are they comparing fuel economy ratings from different countries? Compared with the new EPA ratings (and reality), most ratings from other countries are hopelessly optimistic.
- Are they using a different sized gallon? The Imperial gallon is larger.
Often this is done implicitly - the poster won't even mention the hybrid in their comparison. That way when you look up (or remember) the fuel economy ratings of the hybrid, you're likely to use US-EPA sources.
Yeah, right. Try starting and stopping the engine at every stop light when it's forty below zero outside
It's a trivial engineering task. Prius, for example, has auxiliary electric heaters, and it maintains the engine temperature (and battery charge) automatically. If it's -40C outside the ICE will run a bit more, and that's all. This shouldn't be of any concern to the driver unless he lives in Alaska; then he'd be getting worse MPG than people in California do.
And on the subject of starting a cold ICE in cold weather. Hybrids start the ICE at higher RPM, and they have 100x power of a standard starter. So if the ICE in a hybrid doesn't start it's because something is broken, not because your battery is frozen solid and the starter barely spins the crankshaft.
That's for the Mazda2 you can buy right now, not the one coming down the pipeline.
Not a typewriter
If the article had been about an award the Mazda had received, you'd have a point. As it stands, it's about the potential MPG rating, which the TSI engine doesn't approach. So you posted a non sequitur.
That's nonsense.
1. they have caught on very well, thank you very much, everywhere except the US, and that's because the US was slow in adopting the low-sulfur diesel fuel needed by modern diesels.
2. if anything, the diesel will have longer gearing than the petrol version to take advantage of all that torque at low revs. Since turbochargers have become common on diesel engines sometime in the '80s, diesels have had easily enough power to cope with the most demanding driving conditions.
The reason the UK tests give a higher MPG figure is because a "gallon" is defined differently in the UK..
See http://en.wikipedia.org/wiki/Gallon
70mpg is misleading for this automobile, as is the article. These numbers are based on the Japanese test cycle, which also states the Toyota Prius achieves 89 mpg).
src : http://wheels.blogs.nytimes.com/2010/10/21/mazda-next-generation-mazda-2-will-get-70-m-p-g/
-- cut --
The Mazda release said the car would achieve 70 miles per gallon, but that number was based on the Japanese test cycle, meaning American mileage would be lower. A 15 percent increase from the existing Mazda 2 would result in a combined 37 m.p.g. (For comparison, the Toyota Prius, which gets a combined 50 m.p.g. from the Environmental Protection Agency, achieves 89 m.p.g. in the Japanese test.)
-- cut --
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
I saw this yesterday:
http://www.nyteknik.se/nyheter/fordon_motor/bilar/article2494299.ece
http://www.nyteknik.se/incoming/article2494304.ece/BINARY/original/airmotion700.jpg
http://www.nyteknik.se/incoming/article2494301.ece/BINARY/w468/airmotion468.jpg
Also this:
http://www.engadget.com/2007/05/27/indian-air-powered-city-cat-car-prepares-for-production-run/
"68MPH and a range of 125 miles"
On pressurized air ..
Those older vehicles were not light. The bodies were made from cold rolled steel, with solid I-beam construction.
That was my first reaction too, but I looked it up. The VW Golf debuted at under 1900 lbs, and stayed under 2200 through the mid 80s. The current Golf weights over 2900 lbs. Older economy cars were definitely lighter than the current ones, which is what he was talking about.
They got similar or better fuel mileage due to the lack of restrictive emission add-ons
I don't buy that. The emissions add-ons were the worst in the 70's right after they were first required, and have gotten better since then. My parents got 50% better gas millage by removing the air-to-exhaust-injection system and catalytic converter on their Jeep J-10 pickup. Loosing the catalytic converter on a current Toyota Tacoma had negligible affect on fuel efficiency.
Furthermore, newer cars aren't "safer". They handle better and are more controllable due to innovations in suspension and steering, and have a safer compartment resulting in better safety, but the vehicles themselves are less likely to survive even a 'mild' fender bender without thousands of dollars in a rebuild.
In other words they are safer in every way, but they sacrifice durability to obtain it.
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.