Compression ignition gas engines?

[habu987]

I wonder if we're going to see any of the Big 3 adapting this technology to their engines? Now that Mazda has shown it's possible, I'd love to see the Big 3 take the SPCCI concept and run with it, with their substantially higher R&D budgets, since it looks like it solves the HCCI puzzle.

The engineering details are over my head, but would an engine with SPCCI/HCCI be able to handle the engine load that comes with towing? If it can, and isn't prohibitively expensive or complex to implement (and is sufficiently durable), sounds like a slam dunk to implement across the board on all engines.

Looking at the Mazda 2.0 example from the article, (assuming the 2.0 engine has the same base output with or without the SPCCI tech), Mazda purports a ~22% increase in power, 38% in torque, and 30% in efficiency.

Presuming Ram could implement the same technology and it would work in a truck's use case and be able to put up similar improvements in V6 and V8 applications, going with a slightly more conservative estimate of 15% increases across the board, resulting in great hypothetical numbers:

• 3.6 V6: 350 hp, 309 ft-lb, 24 combined mpg
• 5.7 V8: 454 hp, 471 ft-lb, 19 combined mpg

https://www.caranddriver.com/news/mazdas-gasoline-skyactiv-x-spcci-engine-explained

 

[SpeedyV]

Hmm...”dieseling” a non-diesel. Gotta build a bulletproof motor to handle those pressures. Would it come with diesel-like pricing, too?

 

[habu987]

Hmm...”dieseling” a non-diesel. Gotta build a bulletproof motor to handle those pressures. Would it come with diesel-like pricing, too?

No idea about the pricing. My understanding is that Mazda claims the 2.0 Skyactive-X will be roughly the same price as their 2.5 upgrade engine, which looks like a ~$2k upgrade over the base 2.0, but that engine upgrade is also bundled with a trim upgrade. The 2019 model is supposed to be unveiled next month at the LA Auto Show, I would expect pricing to be announced not too long afterwards.

If Mazda is able to keep the price under control, with their limited budget, I would think a Big 3 application would be able to come under diesel upgrade pricing.

 

[SpeedyV]

No idea about the pricing. My understanding is that Mazda claims the 2.0 Skyactive-X will be roughly the same price as their 2.5 upgrade engine, which looks like a ~$2k upgrade over the base 2.0, but that engine upgrade is also bundled with a trim upgrade. The 2019 model is supposed to be unveiled next month at the LA Auto Show, I would expect pricing to be announced not too long afterwards.

If Mazda is able to keep the price under control, with their limited budget, I would think a Big 3 application would be able to come under diesel upgrade pricing.

Keep in mind the duty cycle requirements of a truck...

 

[Agitated]

I am very interested in what Mazda has done and I will be watching it for quite a few years before concluding whether I like it or not. I mean the rotary engine is cool and all but......

 

[SpeedyV]

I am very interested in what Mazda has done and I will be watching it for quite a few years before concluding whether I like it or not. I mean the rotary engine is cool and all but......

Gotta give them credit for some crazy engineering innovation...whether the ideas pan out or not!

 

[habu987]

If this idea pans out, I do expect the Big 3 to jump all over it. If Mazda, with it's ~$1.2B R&D budget, can figure out how to finally make compression ignition work for passenger cars, I'll bet FCA's roughly 3x larger R&D budget, GM's roughly 6x larger R&D budget, or Ford's roughly 6.5x larger R&D budget can do some magic with the technology and figure out how to adapt it to truck use, if the technology is at all feasible.

 

[Gman]

I have my doubts as to the effectiveness of the solution.

To maintain stability and prevent pre-ignition, I see requirements for high octane fuel. They'll also have the same problems as a standard Otto-cycle ICE in that the operating environment controlling the combustion will not remain pristine. Carbon deposits/residue from combustion can create hotspots that may prematurely ignite the fuel during the compression stroke.