Mazda's saving dino juice engines by going beyond petrol and diesel

"tapzz" (tapzz)
03/22/2014 at 21:54 • Filed to: mazda, skyactiv

Skyactiv is out now, but only the beginning. From here, it gets freaky. As in: no coolant.

Engine geeks will know that Mazda is foregoing battery anything by betting on new internal combustion engine tech. The current Skyactiv engines already do that by having very high compression rates for petrol engines, and very low ones for diesel.

For the diesel engines, reducing compression to 14:1 means much lower burn temperatures, which means fewer NOX and particulates, which means that the Mazda diesels can do without complicated additive injection systems and still meet the latest norms. Not that they're trying in the US, but hey. Also: 20% more efficient than pre-Skyactiv-D oil burners.

For the petrol engines, raising compression to 14:1 means a more complete, efficient burn, with lots of trickery like funky pistons to prevent the engine from 'knocking'- i.e. self igniting at the wrong point. Result: 15% more efficient than previous Mazda engines under low or medium load (except in the US where the compression ratio is 13:1, because crap petrol)

And according to !!!error: Indecipherable SUB-paragraph formatting!!! and !!!error: Indecipherable SUB-paragraph formatting!!! , that's where they're going for the second generation of Skyactiv: they'll let petrol engines self-ignite – just like a diesel – in most situations; i.e. less than half load. When really giving the engine some welly, though, spark plugs are still called for. Moving from self-ignition to sparks seamlessly and smoothly is what Mazda's working on now. Result: 30% efficiency improvement over current Skyactiv engines.

Mercedes are also working on such a freak of nature, and they refer to it as diesotto - 'diestrol', or 'gasel', if you like.

But the Mazda guys are looking beyond that to the generation beyond: homogenous ignition. Rather than have the dino juice ignite from a spark (petrol) or an injector's jet (diesel), it all self-ignites at once. Advantage is that there's optimal thermal efficiency, to the point where they're thinking they'll need to insulate cylinders to make the whole ignition process as efficient as possible.

Result? 30% greater efficiency over second generation Skyactiv, meaning cars that will be cleaner 'well-to-wheel' than full electric vehicles. Or so says Mazda.

Will this trickery save 'proper' engines in the long term? Who knows, but it'll be fun to watch.

Images: Mazda

DISCUSSION (79)

Velocity- Peuguette Connoisseur > tapzz
03/22/2014 at 22:06

Mazda is insane and I'm lovin it

vicariousILive > tapzz
03/22/2014 at 22:37

Great write-up!

These guys at Mazda are really thinking outside the box and it's great. They are looking into the ICE and making the process more efficient rather changing the fuel type, remember E85 anyone? Yeah I almost forgot about it myself. I understand we are dependent on fossil fuels but hopefully these breakthroughs will allow us to use our natural resources more efficiently while in the mean time develop a better alternative means of personal transportation.

I got kinda lost there for a second I am assuming that by "homogeneous ignition" you mean that the oxygen and fuel molecules are evenly dispersed in the combustion chamber with no pressure differential in the combustion chamber?

For better insulation I say we try to use Reaction Cured Glass (RCG). That's the stuff used on the space shuttle tiles. Has a damn low thermal conductivity. That will make combustion as adiabatic as ever.

BJ > tapzz
03/22/2014 at 22:51

Very interesting, thanks for sharing this!

Squidy > tapzz
03/23/2014 at 08:42

Looks nice, but do their cars still rust away within 5 years?

GFFFFF > tapzz
03/23/2014 at 08:49

So my understanding is that they want to increase the temperature inside the engine block with new materials purposefully to make a more efficient burn? Mazda is always doing something great, that's the reason we need small car companies in this world. It keeps the occasionally stumbling big boys on their toes...unless you're GM of course.

Daveinva > tapzz
03/23/2014 at 08:53

Big whup. For years Ferrari's had advanced technology that ignites the fuel even before it gets to the cylinders.

Kinja'd!!!

Vie Ventar > tapzz
03/23/2014 at 09:05

Kinja'd!!!

Ah, beloved Oxigen.

It's like Oxygen, but more easy to trademark!

jimz > GFFFFF
03/23/2014 at 09:09

Rate of heat transfer between two "things" is heavily influenced by the difference in their temperatures. Running an engine hotter reduces the amount of heat lost and improves efficiency.

Oh, and GM has been working on these very things too. In fact, they've already demonstrated running cars with the "diesOtto" concept, except GM calls it HCCI.

jimz > tapzz
03/23/2014 at 09:13

Mercedes are also working on such a freak of nature, and they refer to it as diesotto - 'diestrol', or 'gasel', if you like.

GM has been working on it too; they call it HCCI (Homogeneous Charge Compression Ignition.)

Chief Illiniwreck > tapzz
03/23/2014 at 09:22

Self-ignition? I think I would have expected that from Tata rather than Mazda...

LongbowMkII > tapzz
03/23/2014 at 09:23

This only makes sense if they use black magic.

im now eagerly awaiting the sky active rotary with 50 mpg and exhaust that smells like apple pie.

Jojoma12 > Daveinva
03/23/2014 at 09:31

Um...

ZabiakFero > tapzz
03/23/2014 at 09:49

do I hear hydrogen burning rotary?

solaar > Jojoma12
03/23/2014 at 09:53

Haha

Aaron Short - PROUD OF LEYLAND > tapzz
03/23/2014 at 09:56

Mazda and ford really are leading the way for petrols, battery tech is not currently advanced enough for electric cars to be truly viable or even environmentally friendly!

The pollution caused by mining the metals and minerals needed for batteries is insane!

New tech is always nice, but its always alot more efficient for now to develop and build the stuff we have (while developing new tech, so we dont launch it immaturely), think of the energy needed to change a plant to build electric/hybrid vehicles, and the new processes needed to recycle them!

Hybrids are all nice, but if the engine powering the batteries isnt as efficient as possible, then whats the point? Imagine a hybrid with a lightweight ICE thats at the limit of possible thermal efficiency with low CO2 and a lightweight battery that can hold up to 200miles of charge, in a car with efficient bearings, tyres and low drag, with energy recovery systems also fitted.

400mpg+ and 50kg> CO2 would be possible, imagine driving from lands end to Edinburgh on two gallons of fuel!

Brickman > Velocity- Peuguette Connoisseur
03/23/2014 at 09:57

Most other car company's try to innovate by putting more electronics and bigger touch screens, Mazda innovates what we really need.

Have Jeep, will travel. > tapzz
03/23/2014 at 10:02

Glad to see Mazda allowing their engineers play. Sounds like they are on to something.

It's so cold in the D > vicariousILive
03/23/2014 at 10:04

For diesels, lower compression ratios actually mean higher particulate emissions and lower NOX emissions. That's the engineering trade off you're making when you pick your compression ratio. Raise it to reduce soot but then you get higher NOX (requiring an SCR system), or lower it to reduce NOX (don't need SCR) but then you have to deal with more catalysts to filter the soot.

tapzz > vicariousILive
03/23/2014 at 10:17

My understanding is that Mazda's homogeneous charge compression ignition (HCCI, just like GM) is not just about the even distribution of oxygen and fuel, but also about getting the mixture to go 'bang' of itself, all at the same time. I suspect that you get the latter from the former, but that's a bit beyond what I know.

tapzz > It's so cold in the D
03/23/2014 at 10:38

That's interesting. According to the (German) Heise article, homogeneous ignition lowers the temperature, which means less NOX, but also causes fewer particulates because there are no fuel droplets, so that all fuel molecules can react with oxygen properly. But that was in the context of the Skyactive II dietrol Frankenstein engine. What I'm guessing is that Mazda have somehow managed to get the fuel to disperse very evenly in their current Skyactiv-D engine.

tapzz > Vie Ventar
03/23/2014 at 10:48

Heh. I suspect that's what linguists call 'first language interference': Japanese only has "shi" ( or ) to approximate the "xy" sound, so mapping that sound back to English in the western alphabet might get a little random sometimes.

Insurance Joe > tapzz
03/23/2014 at 10:50

When do we get a Skyactiv rotary?

tapzz > Insurance Joe
03/23/2014 at 11:03

I like to think there is some otaku engineer in Hiroshima who has offered twenty years of weekends and evenings to making a Skyactiv rotary happen.

vicariousILive > tapzz
03/23/2014 at 11:34

To go bang at the same time you would need to have theoretically the same pressure in the combustion chamber at the time when it reaches the auto ignition pressure. Keeping it the same temperature would help keep the same pressure too.

ratpie > tapzz
03/23/2014 at 11:38

Let me just say that Mazda's certainly not the first company to have looked into these technologies.

The so called "2nd generation" skyactiv engine is essentially a homogeneous charge compression ignotion (HCCI) engine, which actually has been research since the early days of ICEs.

As for the 3rd generarion skyactiv, a coolant-less fully insulated engine has also been researched since the 80s (based on my knowledge, it could be even earlier).

However, researh is one thing, putting it to production is another. I really hope Mazda follows through with this and not just let it become a marketing strategy for publicity.

TownaceNoah > Jojoma12
03/23/2014 at 11:44

Yeah, right?

tapzz > vicariousILive
03/23/2014 at 11:52

Ah! That would explain the need to insulate the cylinders for the 3d generation Skyactiv engines.

All Motor Is Best Motor > vicariousILive
03/23/2014 at 12:04

RCG is very weak and said weakness resulted in the loss of Space Shuttle Columbia and all of her crewmen. Not an expert, so I don't know if it can be made strong.

justregisteralready > tapzz
03/23/2014 at 12:05

Getting closer:

http://www.hotrod.com/techarticles/e…

I just can't believe it's taken nearly 30 years for engineers to come back and try a similar route to this engine concept.

SensousLettuce > vicariousILive
03/23/2014 at 12:13

Another potential bonus of insulation is rejecting less heat to the coolant (low heat rejection, or LHR). This keeps more energy in the exhaust stream that can be used to turn a turbine. I know Mazda has yet to add a turbo to the gasoline engines, but this might be a future consideration.

David > jimz
03/23/2014 at 12:21

...and the Koreans: http://www.autonews.com/article/201311…

vicariousILive > All Motor Is Best Motor
03/23/2014 at 12:24

We'll actually it's very strong since it can handle a one of the harshest environments. A damaged tile from fell off of Columbia and the substructure at that point could not handle the reentry environment. It was the absence of the tile that caused the failure of Columbia not the weakness
I mostly meant it as a joke but at the same time if you could somehow find a way to make the bore surface out of the same material that would reduce the thermal conductivity that would make the system more efficient, thermally.

vicariousILive > SensousLettuce
03/23/2014 at 12:30

Oh yeah turbo! Now we're talking. I didn't even think of that

RuiGonc > Insurance Joe
03/23/2014 at 12:38

Skyactiv-R

All the wants

frankfan42x > tapzz
03/23/2014 at 12:39

Astounding, especially coming from a smaller automaker. Mazda is small enough to be innovative at their core, knowing that they don't have the deep pockets needed to fund all the hybrid tech. They have gone from an also ran to at the least the "gearheads choice" in the small and mid sized family priced vehicles. This is very similar to what happened in the 60s with small Chrysler innovating with their engine technology. To see if that branch bears fruit go to any dragstrip in America with top fuel, the old Hemi still reigns.

Astounding, but really nothing new. The legendary Smokey Yunick once came very close to marketing a retrofit kit for a 2.5L four cylinder GM engine with many of these advantages. Technology in this case is just catching up to his vision from so many years ago.

Odin the S60RD > tapzz
03/23/2014 at 12:56

Has anyone else thought that if our gas is crap then maybe we should improve that? We all know good gas can make a difference in MPG also.

SportlineJD > tapzz
03/23/2014 at 13:37

Kinja'd!!!

Hmm, is this different than oxygen? (just being cheeky)

Audistein > tapzz
03/23/2014 at 14:00

Kinja'd!!!

HEMI!

Cé hé sin > Odin the S60RD
03/23/2014 at 14:25

That's more to do with pricing there. You have several different octane levels and people are very keen on being able to use the lower and cheaper ones. Which is fine, but there's a downside to this. I don't know what happens elsewhere but in any place in Europe that I've been the minimum octane is 95 RON and I'm guessing that this is the kind of thing that Mazda are referring to, that is that having to design engines to use low octane fuel makes it difficult for them to use all their fuel saving technology efficiently .

ffoc02 > GFFFFF
03/23/2014 at 14:26

Ford was working on something similar years ago. They were attempting to run the engine at 300 degrees, but this being Ford in the early 90's, they couldn't produce a head gasket that could handle the heat so the project was scrapped.

Autojunkie > tapzz
03/23/2014 at 15:10

HCCI

A few manufacturers have had some sort of this system under development for some time now even before Mazda. Hopefully we'll see it transition into production by the next decade.

http://en.wikipedia.org/wiki/Homogeneo…

EffKinja > Insurance Joe
03/23/2014 at 16:05

I talked to a Mazda guy at the car show this year, and he confirmed there is a Sky-R engine. We may never see it, but they have engineers working on it.

joekitch > tapzz
03/23/2014 at 16:17

so this what the bleeding edge of ICE engineering looks like? this is some pretty wacky stuff

Sidewinder1018 > tapzz
03/23/2014 at 16:38

Honda actually had some major research into this for their 2-stroke race bikes. Then Yamaha came out the the YZ426 and everyone jumped on the bandwagon, which I find funny because Yamaha, who made the first 4-stroke race dirtbike, is also one of the few companies that still makes two-strokes.

Honda could make 2-stroke motors that are not only more powerful than their 4-stroke brethren, but also more efficient and cleaner running too.

Take a look at this article from this website: http://www.dirt-bike-tips-and-pics.com/future-of-two-…

"Let's look now at what Honda was doing just before they announced to the world, "No more two-strokes!" The story really begins a long time ago when people discovered that two-stroke engines would sometimes run without spark-ignition. That is, one could pull off the sparkplug lead, while the engine was running, and it would continue to run as if nothing had changed. People said, "It's dieseling."

Actually, what was happening was very different from combustion in a diesel engine. The phenomenon was best explored by Shigeru Onishi in the 1970s. He called it "Active Thermo-Atmosphere Combustion (ATAC)." He said, "With ATAC the fuel consumption and exhaust emissions of two-stroke cycle, spark-ignition engines are remarkably improved, and noise and vibration are reduced." He eventually showed that a carbureted two-stroke engine could be more efficient (lower fuel consumption) than a diesel engine. But only within a narrow range of speed-load conditions.

In the 1990s, Honda R&D Chief Engineer, Yoichi Ishibashi, wanted to clean up two-stroke motorcycle engines. He called ATAC: "Activated Radical (AR) Combustion." Onishi's engines ran generators at nearly a constant speed. Ishibashi needed to greatly extend the range where AR combustion was stable. He found that throttling the exhaust was the secret. He developed a 400-cc single-cylinder engine. For real-world testing, several of these EXP-2 engines were put in endurance-racing chassis. They ran in the Granada-Dakar Rally and the Baja 1000. The results were good enough for Ishibashi to press on and develop the engine further.

Two bikes were entered in the Dakar - both finished. As Ely Kumli reported in 1997: "The race results were very good even though the bike was not designed to win races, but to test new technology. When the dust settled, the EXP-2 had earned 5th overall and first in both the under-500cc and experimental classes..."

As it turned out, the second-string riders had been given the better equipment! "Compared to Honda's NXR780 four-stroke twin rally race bike," said Kumli, "the EXP-2 has very similar performance, with several advantages. While the single-cylinder EXP-2 produces 54hp to the big NXR's 71hp, they both make 58 lbs-ft of torque, but the EXP-2 is 118 pounds lighter giving it a slightly better power-to-weight ratio. What all this boils down to is that the EXP-2 has about the same real-world performance as the 780, but with substantially better fuel economy and lower emissions."

As good as that sounds, Ishibashi was just beginning. The exhaust valve prevented most of the fresh charge (fuel-air mixture) from getting lost out the exhaust port, but he needed to scavenge the cylinder with air only, and admit the fuel late in the cycle. He came up with a 'pneumatic injection system' that used a standard four-stroke-type fuel injector. Ishibashi summarized the results: "...PDI-AR Combustion drastically decreases HC emission close to the level of four-stroke, and CO and NOx level is 1/5 and 1/7 of four-stroke level respectively. Furthermore, fuel consumption is improved 15% compared with the four-stroke." His English isn't perfect.

I will add: A Honda four-stroke engine giving equal performance had carbon monoxide emissions 500% higher and oxides of nitrogen emissions 700% higher than his two-stroke. Without an oxidizing catalyst, the two-stroke hydrocarbon emissions were slightly more than the four-stroke's, but with a cat, the levels of HC were the same. The CO levels dropped, but the two-strokes advantage over the four-stroke was actually greater. (NOx is unaffected by an oxidizing catalyst).

Obviously, Honda had a good engineer doing good work. He had one more song to sing before the bean-counters dropped the axe on him...

He did not begin with the long-stroke CR250, but with half of Honda's NSR500V. This was a case-reed road-racing engine with a square bore-stroke ratio - like the McGrath generation YZ250s. Honda said that it made "135-plus horsepower " at 10,500 rpm; about 68-hp for a 250.

If ten-five makes it sound like all the power was on the top end, one rider called it a "torque monster" and said the power was "similar to an open-class motocrosser". This engine was introduced at the first 500 GP, 1996. I have given these details because there has been, at least, the suggestion that the long-stroke 250 two-stroke had reached some sort of a technological limit (at less than 50-hp) and that the 450 four-stroke was some sort of a 'solution' to this 'problem'. In 2005, MotoVerde magazine (Spain) dyno tested the CRF450 and the RMZ450 and got 56-hp and 55.2-hp, respectively.

So this was the basis of Ishibashis new 'environmental conscious power unit'. But he really only used the parameters; he built a new design. He got AR Combustion to work from about 3000 rpm to peak power - meaning that the engine could operate normally within that range without an ignition system! At the very bottom, the sparkplug initiated combustion and his Pneumatic Direct Injection limited HC and CO emissions. The engine made 60-hp at 11,000 rpm.

Because the solenoid injector fed an anti-chamber - not the cylinder - its high-frequency limit did not restrict high-end power. In other words, Ishibashis approach did not require the invention of any new technology, only basic engineering. The technology required existed in the 1970s.

There was a rumor that the NSR500V might be turned into a killer street bike. Of course, that never happened. Instead, Ishibashi was sent off to design Civic door latches, or whatever...

About now, someone should be asking: "If Honda knew how to make two-strokes that are cleaner and more economical than their four-strokes, that do not require any new technology, and that could win endurance races, why didn't they produce them?"

Back in 1984, Steve Anderson (then Technical Editor of Cycle World Magazine) went to Japan for a VIP tour of Honda's (then) new racing R&D facility. There, Takeo ***ui, Design Director, "...made it clear that Honda views itself as a four-stroke company that will not be satisfied until it wins all of its championships with four-strokes." Simply put, the four-stroke engine has been company policy; in fact, it has been more of a religion.

Anderson saw, "...shelf after shelf of oval pistons..." and was told that engines were running "...with at least eight valves per cylinder..." and turbo charging. We haven't heard anything about oval pistons in a long time because, after spending umpteen millions of dollars, somebody saw that it was a really stupid idea. It was a way of getting around the racing rules. Four-strokes couldn't win within the rules, so Honda had to find some way to beat the two-strokes and/or the rules. The trouble was, no matter what the shape of the pistons, or how many valves they could stuff in, or how many rpm they could get out of them, the two-strokes kept getting faster and the four-strokes weren't even able to keep pace.

In 1995, Mick Doohan was asked how much power his NSR500 two-stroke made: "I can't tell you that, but I can tell you that if Honda produced a one-liter motor it would make upwards of 400 horsepower. "

It was about that time, it seems, when one of the four-stroke monks had an epiphany: "Instead of spending more money on exotic engines," he might have said, "which hasn't been getting us anywhere, why don't we just buy the AMA and FIM and make our own rules? For instance, we could require that all two-stroke riders wear their helmets backward - if they can't find the first turn, we have to win!" And that is - sort of - what happened.

Reborn Pyrrhic > tapzz
03/23/2014 at 17:07

"When really giving the engine some welly, though, spark plugs are still called for."

What the hell is welly?

tapzz > Reborn Pyrrhic
03/23/2014 at 17:20

Apologies, that's my British English: "Welly" is from "Wellington boot", i.e. rubber boots. "To give (it) some welly" means to stomp on the accelerator, or generally try make something go faster.

Reborn Pyrrhic > tapzz
03/23/2014 at 17:40

I learned English in England, and I am on a few British car forums and I never heard that expression!

DougNuts > Odin the S60RD
03/23/2014 at 17:44

91/93 Octane is right there at the pump. Tapzz should have said that Americans have no appetite for premium fuel in economy cars, because that's the correct reason we don't get the 14:1 engine.

tapzz > Reborn Pyrrhic
03/23/2014 at 17:46

I feared I may have made it up for a sec, but no: it really is known idiom

DougNuts > ratpie
03/23/2014 at 17:47

Exactly, I was reading about it in Automotive News 7-8 years ago and GM was close. From what I remember, the HCCI works well in narrow powerbands, making it great for CVTs and/or hybrids. There was talk that the Volt was going to be HCCI, but that didn't happen.

samssun > Insurance Joe
03/23/2014 at 18:07

You don't, because most of these developments center around running very high compression, whereas a rotary's fundamental limitation is that it's inherently low compression (which is why it should always be turbocharged).

Cole Paquette > ZabiakFero
03/23/2014 at 18:26

Hasn't a hydrogen powered rotary been in development for a little while now at Mazda? I thought they had something on their website about it.

Reborn Pyrrhic > tapzz
03/23/2014 at 19:29

I believe you. I am by no means an expert in British English! And with the numerous dialects spoken in GB there are lots of expressions like that I haven't heard.

Nick > tapzz
03/23/2014 at 20:40

Cool stuff. Glad to see the manufacturers taking chances and putting some effort into developing new technologies.

Ed Stewart > All Motor Is Best Motor
03/23/2014 at 21:35

Wrong tiles friend. The problem on Columbia was damage to the Reinforced Carbon-Carbon panels on the wing leading edge. Those are nowhere near as fragile as the RCG based LRSI and HRSI on the rest of the ship. Basically, the RCC are multiple layers of carbon fiber laminated in criss-crossing directions, then permeated with a binder that is burned out, leaving a carbon "cement". These suckers are dense and rigid. RCG would actually be great insulation in an engine, as long as it's in some sort of jacketed cylinder.

12GRSTi > vicariousILive
03/23/2014 at 21:42

E85 is not forgotten, it is an oasis of cheap race gas for those of us in the midwest. $2.50/gal for 104+ octane that can take enormous amounts of timing and boost with no knock, burns cooler, and smells nice.

vicariousILive > 12GRSTi
03/23/2014 at 22:21

smells like popcorn?

In the inter-mountain west here I saw a gas station that had a E85 pump. Was there for about 6 months then was replaced by a diesel pump or on second though maybe it was an etahnol-free pump.

gmporschenut also a fan of hondas > tapzz
03/23/2014 at 23:23

6 years ago I listened to a SAE presentation on HCCI. it seemed the major issue wasn't getting the system to run but be able to transition from spark to HCCI without self destructing. Any variation in engine temp (either from increased rpm, enviroment, or airflow) had to be countered with fuel, coolant, and compression adjustments, in order to keep the engine in a perfect "happy zone". Probably why they need extra insulation. The end statement was at the time this could for for stationary load/rpm use but variable loads and speed (as seen in an automobile) would add exponentially more variables to control.

Aenemia > vicariousILive
03/23/2014 at 23:51

I've never understood why "green" energy has to be the future of energy. I don't know why more companies aren't trying to research technology like this that greatly reduce or even eliminates pollutants from fossil fuel use.

I think we should be open to clean energy from any source available... especially cheap, readily available sources.

Nick Leary > tapzz
03/24/2014 at 00:33

Hook those up with ford ecoboost tech and we've got an automotive gold mine!!!

RadiuM > Reborn Pyrrhic
03/24/2014 at 01:51

Give it some Jandal!

tapzz > gmporschenut also a fan of hondas
03/24/2014 at 06:32

I get the impression that Mazda is attacking that problem with a load of sensors and brute compute power.

The stationary load point does rather suggest that a simplified version of this type of engine might do well in range extended EVs.

GFFFFF > jimz
03/24/2014 at 10:11

the difference though is that Mazda will actually put it to market most likely, GM will stuff into a room of ideas and concepts. GM lacks the bravery to control the market, the market of idiotic consumers controls GM. That's why they keep churning out boring plastic laced and bloated vehicles. Because people amazingly like it here in the states.

The Stig's graphic designer cousin > tapzz
03/24/2014 at 10:54

That's not exactly correct.

It is true that the US gets a 13:1 compression ratio, but it isn't because of "crap petrol". It is a business decision based off of the trends of the crap consumers here. With a few exceptions, the majority of the buying public balks at (ie, doesn't buy) anything that takes anything over regular grade fuel. Especially in the economy car market.

Who cares if that extra $3 per fill up will net you better fuel economy and get you better power. If it requires premium, they'll just walk away.

So Mazda USA decided to lower the compression ratio, and the fuel grade requirement, as to not scare off the buying public, aka, idiots. My words, not Mazda's.

Odin the S60RD > DougNuts
03/24/2014 at 13:08

Gotcha. Yea I was confused, I use either 89 (minimum recommended for my truck) or 93 when I could afford it. The article could use an edit that addresses this.

jimz > GFFFFF
03/24/2014 at 13:37

tell me how it's "idiotic" to serve the largest market from which you derive most of your profit? "Idiotic" is expecting an automaker to spend a few billion dollars developing a car that all of a dozen so-called "enthusiasts" will buy. Besides, HCCI is not some "quirky but lovable" thing like the waste of time that is the Wankel; it's a very real way to improve the efficiency of a piston engine and everyone is working on that.

DWFMBA > tapzz
03/24/2014 at 15:18

So the types of cycles will be blurred, but what fuel is it actually burning?

tapzz > DWFMBA
03/24/2014 at 16:50

As I understand it: petrol, even if for no other reason that I don't think you can ignite diesel with a spark under any circumstances

Ike B > The Stig's graphic designer cousin
03/24/2014 at 17:55

Considering how wildly variable the price of premium is compared to regular where I live (anywhere from a 12% to 30% premium), the people aren't "idiots" for not wanting to pay for it unless their car gets way, way better mpg than that car's competition. And I'm talking current vehicles, not theoretical future ones.

It's just like with diesel. In most of America it's such a huge jump from regular gas to diesel that you really need to factor that in when calculating the mpg advantage in that car over the long term.

GFFFFF > jimz
03/24/2014 at 21:58

The rotary is not a waste of time. Someday technology and more importantly materials will exist to allow the rotary concept to serve better and require less maintenance and less wear issues. I'm ok with controlled chaos, and I'm glad someone has tried to play with it. I was stating that the American consumers taste of vehicles is idiotic, and obviously GM is going to build what these clowns demand. They have to make a profit. I'm not asking them to make one off cars for enthusiasts only, but to raise the bar to at least the Europeans level in terms of quality, materials, and engineering. This will require a drastic cultural shift within the company, and within the factories and workforce; who've all been happily shoving plastic and stamped panels aimlessly in poorly looking cars for literally decades now. Bring the craftsmenship back, design interesting cars, and change what American consumers want by actually INSPIRING them to want it.

boneheadotto > tapzz
05/20/2015 at 08:41

Kinja'd!!!

The secret ingredient is apparently Oxigen

edu-petrolhead > tapzz
05/20/2015 at 09:32

Needs more rotors

Kinja'd!!!

Just kidding, this is why I love Mazda! I think they’re the most innovative relevant car company today.

Aaron K > gmporschenut also a fan of hondas
05/20/2015 at 10:55

Sounds like it would initially lend itself better to the charging ICE of a hybrid, easier to keep the engine steady state. Might also be a good way to prove the road worthiness of the HCCI tech.

SasquatchMelee > GFFFFF
05/20/2015 at 12:59

Let me google that for you:

http://articles.sae.org/12970/

mpieman > jimz
05/20/2015 at 19:20

Probably by the same guys that put the diesel technology to a normal petrol engine block.

jimz > mpieman
05/20/2015 at 19:54

#1 the Olds wasn’t a “normal petrol engine block.” it was significantly redesigned for diesel duty, and a hell of a lot stronger than the block for the gas engine. Drag racers used to build gas Olds race engines using diesel blocks because they were so much stronger.

#2 I’d wager almost all of the people who worked on the Olds diesel engine retired 20 years ago.

try to stick to things you actually know something about, you’ll look like less of a fool.

mpieman > jimz
05/27/2015 at 22:35

What block did GM use in all of those cars? While it was somewhat redesigned 350 block, the block needed more design work, and balance of the engine was crap. It was basically a normal but stronger block. They did a little better with the V6, but not much better.

So, if it is easy to slap gas parts on a diesel block, how “significantly redesigned for diesel duty” was the block?

Unreliability and anemic performance seem what came from slapping new heads on a standard block design, using only 10 bolts that stretched, so failures were common. What about 0 to 60 in about 17 seconds? Never having more than 120 horsepower or much more than about 220 pounds of torque were a problem too. Timing train problems and fuel purity problems were common too. Why was there no water separator for the fuel system? There were too many weaker common parts shared with the gas engine. Service mechanics had little to no additional training on these engines, and repaired them like a gas engine. Do I have to mention about the class action law suit?

As for those who designed the engine? Buying a GM supports all of these idiots in retirement. They were probably transferred to another department like a priest to another parish.

jimz > mpieman
05/27/2015 at 23:03

What block did GM use in all of those cars? While it was somewhat redesigned 350 block, the block needed more design work, and balance of the engine was crap.

what the fuck does the block have to do with the engine’s balance? your entire post shows you haven’t the faintest fucking clue what you’re talking about.

mpieman > jimz
05/29/2015 at 10:10

By balance, I am referring to the rest of the engine. Buy a dictionary and use it. The engines were never subject to excessive vibration, (out of balance is what you are talking about, isn’t it?) because the strength was in the torque and not horsepower. If you had read my post you would read that the block was not the problem, but whatever they bolted onto the block was totally inadequate.

Most of those who had the car converted to regular gas, via a new engine and gas tank, could not sell the cars because the DMV and the EPA would not allow the car to be sold. How do I know? When the cars were E-Checked, the computers did not match the registrations. It was all over the news.

As for something built for a quarter mile only, this block rules. You can force upwards of 1000 horse power and torque with a few modifications. One of the reasons that most car builders do not want these blocks today, is that a crate engine with an aluminum block is lighter and the car will be lighter, especially in the front end and will not plow into a corner because of the additional weight the heavy cast iron block will have.