How Mazda Is Saving The Gasoline Engine – SkyActiv-X

How Mazda’s Revolutionary SkyActiv-X SPCCI Engine Works
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The ideal otto engine is something you may learn about in an introductory course of thermodynamics. It teaches important lessons about thermal efficiency, and it’s the ultimate unachievable goal of every engineer who’s ever worked on internal combustion development.

But that certainly doesn’t stop Mazda from trying. With their eyes set on the the ideal engine, they made changes from their SkyActiv-G engine to improve thermal efficiency in seven key areas. Most importantly, it’s the world’s first production implementation of compression ignition in a gasoline engine. More specifically, compression ignition timed with a spark plug: SPCCI. In this video we’ll break down Mazda’s SkyActiv-X engine, and talk about four of the major improvements they’ve made in pursuit of the ideal engine.

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Justin Plunk says:

Will the ideal engine include a combination of as close to possible to hcci plus VCR seen with infinity? Especially given the power stroke transferring the energy almost directly downward with the VCR then maximizing the usefulness of the fuel with spcci, I would think there is a potential for seeing ridiculous increases in efficiency while maintaining potential power output.

Matt Wilcox says:

I’ll buy a horse & saddle before I buy electric……..

Ashmeed Mohammed says:

Could they inject part of the fuel at the air intake stroke, and Then the remainder at the TDC, to trigger off the spontaneous combustion wave?

Tom B says:

I want one!

Xerxez the Tank says:

I have some questions. The first is, would the dynamic pressure turbo that Mazda has been working on, possibly be more efficient than the lean supercharger they currently have for this skyactiv-x engine? The next question I have is, combining their dynamic pressure turbo, and all of the tech of the skyactiv-x, could they make a super efficient v8?

M Ladd says:

Still waiting, zzzzzzzzzzzzzz!
What’s it been 2 years now?

Whisper Mason says:

I bought one in 2012, have 116,000 miles on it. Fuel efficiency around 36mpg under rush hour flipping off your neighbor for cutting you off conditions. 45mpg if your paying attention to fuel economy as staying around the speed limit and not over excellerating. Even better on level interstate trafficless driving. Fun to drive….. No, but that’s not what I bought it for. What I found particularly amazing was 90,000 miles before the OEM Brake Pads needed changing.

Samuel Pope says:

It will work re gas mileage/emissions. But if you manage to get to 100k mi you are one of the lucky ones.. Just like ford Eco boost and all of the other schemes. Wake up people! Sending cars to the compactor at 100k mi and less.. how’s that for your carbon foot print? All of this crap is because Toyota and Honda damn near put themselves out of business in the mid 90s designing cars that last 3-400k miles. It is demanded by the nanny state EPA and manufacturers love the increased unit profitability and designed obsolescence. It’s always about the $$$ in the end.

Li Ryan says:

“A low octane is desirable.” Thinking about those oil companies marketing higher octane fuel as the final premium product

Vincent Bolduc says:

Thanks for explaining it so well! This engine seems promising!

Doug Puchalski says:

exhaust gas is nitric not nitrous oxide

Adrian says:

Does this mean gas prices will go up when this kind of engine goes more mainstream?

Engineering Explained says:

For those with a very keen eye, you’ll notice that in the EPA fuel economy charts (0:45) Hyundai had the highest number in 2013, which goes against the claim of Mazda having the best fuel economy for five years straight. This is because in 2013 Hyundai was under investigation by the EPA for claiming fuel economy numbers that were too high, so they were disqualified. Hope everyone’s having a great day! 🙂
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Rafael Santos says:

imagine if they brought out a smaller engine (90-100HP at 1-1.5L for example) with this tech in the EU. They would sell like hotcakes.

MiG FPV says:

Hi. I have some consumer questions regarding this engine.Could someone explain or predict, what are the maintenance costs of this engine gonna be, or could be? As far as i was told, diesel engines have higher maintenance costs than a petrol engine, but better economy. What about this one? Price wise the forecasts for the skyactiv X engine/car, are speculated to be in between mazdas petrol and diesel (in the EU), as far as i read somewhere online. I am asking because of my mileage i would need a diesel, but because of possible EU diesel restrictions, it is to risky to buy, so the skyactiv x looks like a good alternative. Thanks.

Luke Clayton says:

Maybe my next car will be a Mazda. My only concern is if the electronics fail, will this cause irreversible damage to the engine? Do they have a fail safe that if something goes wrong with one of the sensors it will revert to safe cycles?

Stefano Grillo says:

Ok i lost just 15 minutes for a description of a diesel engine.

M Ladd says:

With that high of a compression ratio what is the odds of that engine even reaching 100k miles?

Rahul Occamy says:

Awesome Engineering Explained .. Thanks

Jay Trenkle says:

Very cool explanation.

Horace Lim says:

FANTASTIC explanation… thanks so much!

Hunter Bacon says:

Bruh could I do this for my xj?

Jay Smith says:

I wonder why there isn’t more technology in natural gas engines. They can handle up to 17:1 compression and forced induction

securitron5 says:

You’re amazing. Great work man, subbed.

S. D. H. says:

Does it gum-up & require expensive, routine cleaning every 30K miles like most direct-injection engines?

SAS RaptorForce says:

Good channel but you talk too much damn uni students

Michael Mace says:

Idk, when I think about Mazda I think about ROTARY engines. Rotary cars are so damn fun to drive. They sound great, they run great, and are so fun to drive. They redline at what, 9K RPM’s I think. Oh right, this video wasn’t about Rotary engines. I think it was GM who almost put out a rotary engine car in the 70s, wish there was a prototype out there somewhere

Don Gillies says:

So the main question is about actual fuel economy vs state of the art Atkinson cycle engines? I presume that 37x +29x air fuel ratio averages to 33x so in theory it can get 2x the fuel economy of a normal gasoline engine at 16x a it fuel ratio?

Bruce Hearn says:

Honda must be collectively shaking their heads. I see what Mazda did and it makes me think of the Honda CVCC (Civic) stratified-charge engine from the 1970’s.

John Ferguson says:

Carbon build-up will cause premature detonation. This engine will never function smoothly after it is no longer new and clean. This technology could work with natural gas fuel.

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