Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

SKYACTIV-X: first commercial gasoline engine to use compression ignition

www2.mazda.com

Post reply on HN
Print view View original

91–100 of 241 posts

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#91

Post by 33W »

elihu wrote: post #62

Maybe this is old news to people who pay attention to car news, but the most interesting thing to me is this line from the press release: > From 2019, start introducing electric vehicles and other electric drive technologies in regions that use a high ratio of clean energy for power generation or restrict certain vehicles to reduce air pollution I've been kind of disappointed that Mazda hasn't gotten into the electri…

They have an interesting somewhat-hybrid called i-eloop that uses regenerative braking and a capacitor to power auxiliary systems:

http://www.mazda.com/en/innovation/technology/env/i-eloop/

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#92

Post by 33W »

ChuckMcM wrote: post #18

A reuters story on how it works: https://www.reuters.com/article/us-mazda-strategy-idUSKBN1AO... So this is 'gasoline' diesel. Or diesel without the NOx. Which, in theory, would give better fuel economy and possibly better torque. And it will ship in cars in the 2019 model year (so possibly as early as late next year). To me, it sounds like a "Don't pass"[1] bet on electric cars. Which they also are working with Toyo…

They also have an interesting somewhat-hybrid called i-eloop that uses regenerative braking and a capacitor to power auxiliary systems:

http://www.mazda.com/en/innovation/technology/env/i-eloop/

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#93

Post by richdougherty »

ChuckMcM wrote: post #18

A reuters story on how it works: https://www.reuters.com/article/us-mazda-strategy-idUSKBN1AO... So this is 'gasoline' diesel. Or diesel without the NOx. Which, in theory, would give better fuel economy and possibly better torque. And it will ship in cars in the 2019 model year (so possibly as early as late next year). To me, it sounds like a "Don't pass"[1] bet on electric cars. Which they also are working with Toyo…

In the linked page they say they're pursuing both internal combustion and electric vehicles and they explain their rationale:

- In line with this policy, continue efforts to perfect the internal combustion engine, which will help power the majority of cars worldwide for many years to come and can therefore make the greatest contribution to reducing carbon dioxide emissions, and combine the results with effective electrification technologies

- From 2019, start introducing electric vehicles and other electric drive technologies in regions that use a high ratio of clean energy for power generation or restrict certain vehicles to reduce air pollution

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#94

Post by jonsen »

ChuckMcM wrote: post #18

A reuters story on how it works: https://www.reuters.com/article/us-mazda-strategy-idUSKBN1AO... So this is 'gasoline' diesel. Or diesel without the NOx. Which, in theory, would give better fuel economy and possibly better torque. And it will ship in cars in the 2019 model year (so possibly as early as late next year). To me, it sounds like a "Don't pass"[1] bet on electric cars. Which they also are working with Toyo…

Someday someone might invent an efficient process for making gasoline from renewable energi sources.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#95

Post by tcdent »

ticklemyelmo wrote: post #88
aidenn0 wrote: post #83

Earlier quoted context omitted.

Almost certainly not, as diesel and gasoline have very different self-ignition properties.

I wonder whether this engine will specifically require you to fill up with NON-premium gas.

To elaborate, higher octane fuel exists solely to prevent self-detonation in higher compression engines by slowing the fuel's burn rate.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#96

Post by flavio81 »

stirkac wrote: post #2

Mazda is one of those companies just don't stop revolutionizing. First they got rotary to be actually usable. Now this.

The rotary was never invented by Mazda, it was invented in germany and applied first by NSU.

Then it was licensed to many manufacturers, among which there was Mercedes-Benz, which was the manufacturer who got solved first the apex seal problem, and in the late 70s with the C111 prototype car, the first manufacturer to create a side port wankel engine (which mazda would only show on the RX8 decades later) and a 4-rotor engine (which mazda would only show on the 787 racing car in 1991.

Then MB ditched the wankel engine because of low fuel efficience, something that ultimately led to mazda doing the same... in the 2000s.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#97

Post by flavio81 »

_ea1k wrote: post #47
mikestew wrote: post #19

Earlier quoted context omitted.

The rotaries leaked oil and got terrible mileage, and good luck finding someone to work on them. Other than that, they were zippy. "Usable" they might have been if you keep a low bar, but "practical" they were not.

Rotary engines do not "leak oil", they burn oil a modest amount of oil by design. If you think about it, there really wasn't another way to lubricate them. Practicality was pretty low, though, as you rightly point out.

Little known fact is also that conventional piston gasoline engines are also expected to burn an amount of oil by design, particularly if given a hard usage.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#98

Post by twblalock »

stirkac wrote: post #2

Mazda is one of those companies just don't stop revolutionizing. First they got rotary to be actually usable. Now this.

Compression ignition is more an evolution than a revolution -- it's an iterative improvement on an existing technology.

Skyactiv exists in the first place because Mazda does not have the money or engineering resources to build a hybrid or electric car by themselves. I suspect that in a decade or two, Mazda's decision not to start building hybrids and electric cars when the other major brands were doing so will be regarded as a serious mistake.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#99

Post by shorodei »

komali2 wrote: post #77
TomMarius wrote: post #74

Earlier quoted context omitted.

I though you Americans have it pretty rough when you're caught going over speed limit?

That's actually a big question I have as a new Californian. In Houston, you got caught, every time , if you sped on the freeways. The cops were everywhere. Here not only do I rarely see cops, I've read in the local papers that cops can't pull people over for speeding if EVERYONE is speeding. You have to be speeding far above average. So everyone is actually incentivized to speed together. When I first got here I saw…

I usually go at 75-80 on a "55" highway for my daily commute, never had issues even while passing cop cars. In general, as long as you're not driving like an idiot (switching 3 lanes without signalling) or running old tags, or basically have a red flag hanging, they won't bother you. Although if they do stop your for one of these reasons, they'll probably also ticket you for speeding. Speed limits are enforced far more strictly in residential areas though.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#100

Post by mchannon »

mchannon wrote: post #31
IgorPartola wrote: post #5

Earlier quoted context omitted.

Did they get the rotary to be usable? I thought even at its best, it was finicky and temperamental. I have never owned or driven one, just doing some idle reading online, so asking this as a serious question.

Owned one. Enjoyed the heck out of it. Lots of torque, lots of pep, though from what I heard, the US version (mine) had substantial increases in pollution controls which hobbled the car. Always first off the line when I wanted to be. Yes, it burned oil by design. I'd add a half-quart of non synthetic 5W-20 maybe every 1000 miles. The rear bumper required additional car washes, as it'd get a black film, no doubt from…

Amazed how many replies the stork comment got.

First off, I agree that the backseat was exceptionally roomy for a 4-door coupe. For adults.

Once you have your first, you realize very quickly that babies come with a LOT of stuff. The first carrier for newborns sticks out a LOT from the back of the seat. The sorcerers at Mazda Engineering made it comfortable for tall people in the backseat by compensating for limited front-back space by using up-down space. This made it impossible for use for an infant unless the front seat was scooted all the way up.

But then there's the stroller. Good luck with that in the comically small trunk opening. Bags of stuff, boxes of stuff, yes, these things are non-optional, and they don't fit in that car, especially all at once.

The final nail was the fact that it's kinda hard to insert a child plus carrier into the backseat with your hands full. Having it back there would've been easy. Getting it back there wouldn't have been. Retrieving it, even more difficult.

After you make your peace with the above, and still manage to cram everything in, bear in mind you still need two adults, not just the driver, to fit in the car at the same time.

We could've done it, somehow, but it was smarter to sell it and buy a cheap used SUV, with plenty of room for everything. It also bears mention that I had used that car as a daily driver for 10 years.

Post reply on HN