Slashdot Mirror
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.
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.
I used to drive an 85 VW Golf Diesel, that Car reliably got (actually got, under real world driving conditions) 47 mpg (5l/100km). That's a car that was build 25 years ago. Volkswagen also sold the Lupo 3L which got 78 miles per US gallon or 94 miles per Imperial gallon
It boggles my mind that 25 years later most cars I can buy in the US get half of what my 25 year old car got. If that. It also means that getting 70 shouldn't be impossible. Thats 3.3l/100km, and it's been done.
> and lots of torque
except with a diesel car you tend to get the torque when you don't need it. And there's also the "diesel lag". Slam the accelerator to the floor - nothing happens - then 2 seconds later a sudden burst of power. Quite fun when your pulling out in a busy roundabout.
Burning fuel while stopped can never be a good thing.
Yeah, right. Try starting and stopping the engine at every stop light when it's forty below zero outside... even aside from the lack of heat inside we quite often see cars that have stalled in those temperatures and simply won't start again.
With the advantage of having no ignition system to go wrong and lots of torque, horse power is a misleading gauge of power, torque is what turns the wheels.
I can produce more torque than a diesel engine with my hands and a long spanner, which suggests that maybe it isn't that useful a figure for determining a car's capability.
And your ignition system may not go wrong, but your turbocharger and much higher pressure injectors can, and do.
Stopping and starting an engine also wastes energy.
It's certainly true if you repeatedly start and stop a car made in 1960's.
But it won't be true if the ICE is designed for that. For example, Prius has no 1900-era DC brush starter, and the ICE can be started with electrical energy or the mechanical energy produced by the inertia of the car. The energy "wasted" to compress the air in the cylinder before first ignition is returned thousandfold in a millisecond.
Well, it's four times what my current car gets. Even if I had to buy premium gas at double the price (it seems to be ~20% higher usually), I'd save quite a bit of money. In fuel anyway.
I save money by purchasing cheap used cars. I'm betting I would have to drive the Mazda a long time before I ever broke even on the purchase.
WWJD -- What Would Jimi Do?
(Smash amp, burn guitar, take home the groupies)
I'd rather take the risk of being killed by someone else than the risk of killing someone else. Moreover, I have serious misgivings regarding the morality of the contrary position.
But how often do you do that? If (like me) you only leave town twice a year, it makes more sense to rent on those occasions.
I can produce more torque than a diesel engine with my hands and a long spanner
That's a nonargument.
Torque figures are just as useful as power figures for comparing cars, i.e. not very much. The meaningful items are the torque curve, which tells you how responsive the engine is over its operating range, and the power-to-weight ratio, which tells you what effect the engine will have in terms of accelleration.
Just because there's a tradition of high speed heavy vehicles doesn't mean it makes sense or is the optimum form of transportation.
However, high speed vehicles overtook horses as a method of transport mainly because of convenience, speed and range. You can travel 300km on a horse, but that would take you more than a day (because your horse will need to rest), but in a car, you can get there in less than 3 hours.
So it is, in essence, a diesel engine - that runs on gasoline. IIRC, diesel engines are around 14:1-16:1 for a DI diesel. I'd wager a guess that they offer (or will offer) a Mazda 2 overseas with the same engine running diesel (with glow instead of spark plugs, of course).
~/ssh slashdot.org ssh: connect to host slashdot.org port 22: too many beers
If you read between the lines, what she's really saying is "We'll get the "good stuff" over here when we're no longer governed by the oil companies. Or, when gasoline hits $9.50/gal in Lincoln, Nebraska. Or, when pigs fly".
You are welcome on my lawn.
I'm not knocking progress but...
This merely represents an improvement in dead-end technology (burning things to go places).
--Richard
They take into account different driving conditions. Diesels are good for hiway cruising, but are terrible in stop-and-go traffic. Hybrids are basically the opposite, and traditional petrol is somewhere in between.
I disagree with this. My old man had a Mitsubishi turbo diesel pickup back in the 80's. It would get close to 40mpg during normal driving, and had enough power that you could spin the rear tires on dry pavement when shifting to 2nd gear under heavy acceleration. It drove just like a gas-powered vehicle, other than having more torque. I also have a buddy that drives a 3/4 ton 4 wheel drive Chevy with the Duramax diesel. It also drives like a gas-powered vehicle.
There is very little difference between driving a diesel or gas rig in traffic any more. Yeah, the diesel is going to be a little noisier due to its much higher compression ratio, but that's it. The newer diesels aren't your grandfather's diesels that had the red line set on the tach at about 2000 rpm, and that's what made them a little harder to drive in traffic as you had to run through the gears very quickly to keep from over-revving the engine when you accelerated.
"while democracy seeks equality in liberty, socialism seeks equality in restraint and servitude." de Tocqueville
I'd rather take the risk of being killed by someone else than the risk of killing someone else. Moreover, I have serious misgivings regarding the morality of the contrary position.
I highly doubt this. Unless of course your collectivist attitude has totally killed off your survival instinct.
Car-2 costs $5,000 more than Car-1 (Note Golf vs Golf TDI)
You may be saving $.03 per mile, but that's going to take you over 150,000 miles to pay back.
Right, everywhere EXCEPT that one big place where the majority of all cars (and miles driven) are...
And even that's not true... Diesels have caught on in EUROPE. Why? Because...
No, it's because the taxes on fuel in most European countries is greater than the actual cost of fuel, and therefore the fuel with slightly less tax burden turned into the most economical by-far. Nowhere outside of Europe is there such high adoption of diesel cars. It's all because of the taxes.
IMHO, all non-CVT vehicles should die off ASAP. You need much less horsepower when you don't get "stuck" in a high gear while trying to accelerate. Not to mention the much more predictable behavior on slick (rain/snow/ice) roads, and less dangerous behavior in cruise control. CVT is so frickin' overdue, it's hard to believe old automatics are still being made.
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
"Indirectly"? There's nothing indirect about a car crash.
As for my views regarding self-preservation, we would live in a far better world if they were shared. Let me make it clear -- I have no problem with killing in legitimate self-defense, or killing in the course of a just war... but choosing a heavier vehicle and increasing risk to the lives of innocent third parties just to decrease risk to yourself leads to a snowball effect where everyone is less safe.
Diesel's actually not that bad. It gets a bad rap because it's used in a lot of truly awful applications, but it's not much worse than regular gasoline when combusted reasonably efficiently - like most modern cars do. Just google "clean diesel" and read up!
/.'s new comment system sucks and won't let me paste anything. It's in the "Fuel efficiency" wikipedia entry, just before "efficiency in microgravity".
/., a site for programming/tech oriented people, such a mass of crap code?
Also, I believe GP misspoke with regards to BTUs/gal - diesel engines tend to be more efficient than petrol engines, to the tune of ~30%.
I'd give you a quote and link you to Wikipedia, but
In other, unrelated news, why is
CVT doesn't have transmission lock, where most decent automatics do, totally eliminating the 'cost' of running an automatic at high speeds.
CVT wastes some energy, energy not lost when using a manual transmission, or when cruising at highway speeds in a modern automatic.
CVTs are cool and fun, especially in-town, but people who drive automatics with autostick transmissions can outperform them as well as manuals.
- Michael T. Babcock (Yes, I blog)