New 2 Stroke with valves from Mazda will blow your mind 🤯

[@fudidle]

Mazdas continued development of creative solutions to small engines is really cool to see. From rotary engines to this.

[@JohnDoe-bd5sz]

Only problem as i have understood it, is these engines need a GPF (Gasoline Particulate Filter) because these engines produces as many, if not more very fine particles. This also means that the idea that Diesel should be phased out because they "pollute" more, is now not correct, compared to petrol engines.

[@cumbob]

​@@JohnDoe-bd5szopf is already in use in europe and probably in the states at some point so its not fonna be just a mazda thing

[@Robdutton91]

@@JohnDoe-bd5szPPFs are already a thing, petrol particulate filters. Just another thing to go wrong and repair down the line anyway. Call it environmentally friendly if you want but it’s not good for the consumer’s wallet

[@JohnDoe-bd5sz]

@@Robdutton91 I agree, but my point was only that now petrol engines also pollute like diesels so the whole "Diesel must die" mob is quite silly. Especially because diesel has lower Co2.

[@Robdutton91]

@@JohnDoe-bd5sz yes you’re right I went off on a bit of a tangent, I agree with you

It's nice to still have a brand that does amazing things.

[@warrenpuckett4203]

The best Mazda. I had was a '94 Ranger, 4 banger 5 speed, stick. I got tired of driving it at 300,000 miles and sold it. It is not often the manufacturers make that kind of mistake. They are in the business of selling cars. Do you wonder why the dealer only keeps a 8 year supply of parts? They will sell the new part at 9 years. IF you buy the new parts wrapped around it.

[@Ratkill9000]

​@@warrenpuckett4203that had the Pinto 2.3L Lima engine. Very robust engine.

[@ShawnKitchen]

It would be even nicer if those amazing things were reliable.

[@kensmith5694]

This is not very "amazing". I am surprised they got a patent on it. All of it is obvious and much of it has been done before.

[@daledavies2334]

In my opinion, Mazda has some of the best engineers in the world. Quite ingenious.

[@yogibarista2818]

The key is direct injection. With the fuel only being injected at the last moment, the rest of it is just an air-pump so having some of the intake lost to the exhaust is not a problem.

[@g8ymw]

Indeed, I believe they are using direct injection on snow mobiles (using the crankcase to charge the cylinder so air/oil enters the engine through the ports)

[@Eduardo_Espinoza]

Ya, I always thought Detroit Diesel engines were perfect minus the lack of a turbo, but the ports were the only problem from it being a hungry oil burner like some modern engines from reputable brands, lastly if seems like octane ratings won't matter any more like a diesel engine, possibly a great contender to the Tesla plaid! :)

[@Wingnut353]

@@Eduardo_Espinoza FYI ports aren't really a problem... Achates power's engines (which cummins is making a military tank variant) has ports and doesn't burn significant oil.... the difference is all in tolerances and our capability to machine these things today. We use thinner oils also... its also doing direct injection like most diesels (except pretty old ones that had pre combustion injection chambers.

[@Eduardo_Espinoza]

Is that also a commercial engine that's used in a tank, so that it has emissions to follow? I wonder if tanks have to follow any sort of emissions. Also, thin oils are efficient, so more power. Lastly, if it's expensive to make it's harder to commercialize it for the masses. @@Wingnut353 I will look into though, so tnx for that info! 🙂

[@kurt5490]

It's called scavenging.

[@benruether8294]

I love how Mazda has always been brave enough to step outside the engineering box that other manufacturers stay in.

[@stravis3269]

Yokinihong. Japan research. Wong long duang

[@nigelcairns6203]

Except the EV box?

I remember Toyota doing six cylinder 2-stroke research engine with valves and a blower already back in the 90s

[@theairstig9164]

Try 1988

[@djhrjeiwhri]

With valves? Direct injected? Compression ignited???

[@hugobloemers4425]

Sometimes a good idea comes too early for it's time. Leonardo da Vinci tried airplanes for instance.

[@user-vp1sc7tt4m]

Not like Mazda does in taking it to the next level as they always do.

[@froggy0162]

Orbital Engineering in Australia did this as well. Sold the design to GM who shelved it…

[@edim108]

Good to see that Internal Combustion is yet to say its last word with multiple companies trying new things to improve the efficiency. And a small bonus that would sure please a lot of the car enthusiasts is the sound of a two stroke!

[@RobertTwiss51]

I agree! And these improved internal combustion engines are ideal for use with the carbon-neutral synthetic fuels which are also in the pipeline!

[@kenmoncrieff3044]

why would it sound like a 2 stroke?

[@BIGSMOKE-bl2lq]

​@kenmoncrieff3044 na it wont no expansion chamber and if they produce it will be a pos under performing mazda and be loaded with mufflers probly wouldn't sound nice anyways

[@Minecrafter-uh6qv]

@@BIGSMOKE-bl2lq ?? Even without an expansion chamber, 2 strokes have a special sound

[@BIGSMOKE-bl2lq]

@@Minecrafter-uh6qv yea but it gets real hard to distinguish with multiple cylinders and mufflers etc i also would imagine it will be fairly tame compared to a mx bike it will just sound like shit i would bet money on it

[@kiefershanks4172]

It should be noted that on the 2-stroke diesels on the locomotives I work with, the supercharger has a centrifugal release clutch on the impeller so that when there is sufficient exhaust gas, the supercharger can act like a turbocharger. When the engine slows down, the clutch re-engages so enough air can be supplied to keep it running. It is actually most efficient at WOT as a result as exhaust gas energy is feeding the engine, not the crankshaft. On a smaller scale, this could make one hell of a powerful engine for a car and perfect for a sports car. Rotary replacement incoming?

[@titibobo2000]

I can add that very big 2-stroke diesels in ships don't have engine-driven superchargers. They use turbo chargers for normal load and additional electric motor-driven air blowers for low loads.

[@matsudakodo]

​@@titibobo2000Mazda is experimenting with electric compressors as well

[@autonomousindividual7780]

Yes, and those old units are better to run than any of the new stuff with tons of computer controls.

[@558vulcanxh]

GM 710 I bet, 😊

[@robin8559]

EMDs

[@bigpicture3]

Detroit Diesel had two stroke engines in 1939 where the breathing combustion air never went into the crankcase. They used a Roots blower to achieve positive air induction pressure. This is just a variation of that design with intake valves, instead of cylinder ports.

[@ronniedale6040]

I am sure this is being done due to size constraints to operate as an apu range extender on EV cars. Operating at a constant speed would eliminate many issues inherent to this design in a conventional application

[@needmoreboost6369]

As would electronic control of the valve timing combined with direct injection! the inherent flaws would be significantly reduced over a fixed timing arrangement and port injection or carburettor for fueling

[@jo-qp7mz]

Nope it's Mazdas sky active x engine in regular cars no hybrid bull shit.

[@jo-qp7mz]

​@@needmoreboost6369Mazda has both those in their new sky active engines this is the newest version of that!

[@Eduardo_Espinoza]

Ya, sadly I believe you're right on that one, since that they mentioned the cams are now 1:1 to the crank, it's spinning 2x the conventional speed so 5krpm is red line 10krpm! Racing cam speeds! So to fix that Mazda's gonna have to put super stiff springs for 14k-21k rpm! Yet, hopefully they can commercialize F1 air valve shocks for that!:)

[@scooter979represent]

Ok so can we get this but with a oil style catch can on the exhaust with a pump that re puts it back into the fuel to reduce waste ?

[@andrepienaar6459]

Ground breaking stuff. Mazda is one of the few manufacturers that pioneer new engines.

[@mattt198654321]

One of these days, one of their engine designs are going to change motoring forever. It's not a matter of if, just when.

[@Fransenn]

this isnt new.

[@3RTracing]

nothing new here. EMD has had this technology since the 1930's.

[@TheYamaha37]

Haha yeah "pioneers"

[@bobcornford3637]

Ground breaking? You must be joking.... it's a uniflow 2 stroke.... been around for years.

[@battleaxefabandmachine]

Detroit diesel did it starting in 1938 and are still being used off road. You can have everything from 1 cylinder to v12 with 1 block or combine blocks for v16, v24 and so on. It is the longest running engine in trucks. All the way to the 80's and in the 90's for special equipment like fire trucks.

[@jamesbosworth4191]

GM Buses also used the Detroit. I have driven many a truck with one of those engines.

[@battleaxefabandmachine]

@jamesbosworth4191 oh yes they did. For decades. Engines laying on their side. Lol. I sold a 6v71 bus engine a few years ago.

[@Anax100]

They also do a good job of running away if they get too high in rpm.

[@chehystpewpur4754]

bull chips. bro they are still used to this day.

[@davidbrayshaw3529]

One of the best sounding engines ever built! But fuel efficiency wasn't a strong point. Acceleration was strong, for a diesel, and the power to weight ratio was commendable. It surprises me how many of these found their way into stationary applications, but they did.

[@mickvonbornemann3824]

Actually 2 stroke aero engines were made with supercharger scavenging & direct injection about 80 years ago, so 2 stroke petrol engines without crankcase scavenging have always been around in some form other. Also it’s possible to use a turbocharger for base rev scavenging. One just has the turbocharger’s axle connected to the crankcase with varible gearing, so it operates like a supercharger at low revs & provides added power to the crankshaft at higher revs, in aero engine circles, called turbo-compounding.

[@Losingsince]

Rolls Royce Crecy

[@1Longranger]

Napier Nomad

[@558vulcanxh]

Rolls Royce and Napier did this in the 1940s, but turbines made them obsolete for aircraft, pity 😮

[@We-Do-NOT-Consent-303]

The invention in this case is not the supercharged two stroke concept. It is the valve CAM control that is different here.

[@catchnkill]

@@We-Do-NOT-Consent-303 Not that. In the patent description, this engine use dual-mode ignition. It uses compression ignition i.e. the diesel engine way in low load and uses spark plug for ignition in high load situation.

[@mickwolf1077]

Mazda said there is still more room to develop combustion engines. once they get the ecu algorithms sorted this should be a sweet engine with double the torque compared to a similar sized 4 stroke.

[@actionjksn]

Most engines are between 30% and 40% efficient. I think most are closer to 35%. So there is a lot of efficiency that can be gained from gas engines. Gasoline is a very dense form of energy. They just need to do what Mazda is doing and improve the engine radically.

[@Wingnut353]

@@actionjksn We already have 45+% efficient gas and diesel engines developed.... just nobody is building them except for military applications, china also has 50% efficient diesels in production. Also part of the reason current diesels are inefficient is excessive after treatment instead of just cleaning up the initial burn.... it wastes a lot of power.

[@actionjksn]

@@Wingnut353 That's better but it's still pretty low.

[@chrissmith2114]

Almost double the power because of double the number of power pulses, but not double the torque ( or maybe even any extra torque ) because torque is a product of crankshaft throw ( engine stroke ).

[@PaulSmith-zx2ru]

I think these engines like some others I've seen recently will be utilised as range extenders in hybrid vehicles basically used as a very economical and environmentally responsible generator. What a shame Mazda didn't release this 20 years ago instead of the rotary engine but it shows they are constantly looking at improving engine technology.

[@michaelbuckers]

Pretty sure the only reasonable range extender design is rotary. Fuel efficiency and reliability is not at a premium for those and you don't want it to be any bigger and heavier than it absolutely has to. Otherwise you're just running a plug-in diesel-electric so you might as well lean into it and use a proper big powerful ICE. Also this superchaged two-stroke requires a supercharger, it makes it even bigger and superchargers don't exactly have great reliability. So that actually works against it in terms of range extender applications. You get maybe equivalent of atmospheric rotary in much bigger heavier package and with the same level of reliability, and it saves, like, what? Half a gallon of gas? In how long?

[@Noneofyourbusiness2000]

No.

[@swilleh_]

shut up! we like rotaries! They are the best!

[@glike2]

A small and efficient one or two cylinder REX might have a small niche with HEV trucks for towing

[@octagonPerfectionist]

@@michaelbuckerswhy would you use a rotary engine when emissions and efficiency are so poor for them? you ideally want the most efficient possible tech that’s a better balance of weight vs efficiency

[@henrymach]

I'm glad to see that development in combustion engines hasn't stopped even with current EV obsession

[@noname7271]

EVs will need range extenders for a long time until the grid is upgraded. This wpuld be an awesome APU in a tiny paclage on an electric, even as a regular portable generator.

[@JohnDoe-bd5sz]

@@noname7271 What range extenders. I drove 3000 miles on a round trip to Italy this summer, and i had NO problems charging my EV, i was even able to just go past the charger it suggested as there was still another one within range.

[@noname7271]

@@JohnDoe-bd5szThis wouldn't work as well in a sparse wasteland like Middle America.

[@danharold3087]

@@noname7271 Yes but that will change. Not long ago I would have had to go out of my way to get from OK to ND. Not anymore. Not saying we are there yet but I expect it will not be more than a few years. I am keeping my gas cars till then. Will not hesitate to go EV when it makes sense. Middle America IS sparsely populated but it is anything but a waste land. But happy to have the rest of the country think it is. Mazda should be investing in the future. The Japanese government has been slow to support the adoption of electric vehicles (EVs). This is due in part to the lobbying efforts of the Japanese automobile industry, which is heavily invested in internal combustion engine (ICE) vehicles. Same old story. Think crushing of the EV1.

[@noname7271]

@@danharold3087 Eventually yeah but distances are greater in North America compared to a European county.

[@kensmith5694]

2 stroke that doesn't burn oil is an idea that has been around for a long time. It is common in diesel engines. They use a blower to move the air into a manifold that goes to the cylinders. On that sort of design there often is a port in the side of the cylinder for in take but vales in the head for exhaust. On the Deltic rail engine both intake and exhaust are ports but they use two pistons per cylinder and time them to get the ports to open at the right times. A turbocharger can be used on such an engine. At high RPM, it pushes air into the blower increasing the air pressure in the manifold. This is a good idea because with less time to purge the exhaust you need to work a bit harder to get the clean air in. On a piston port, there is no need for there to be oil leakage. The oil ring never goes above the port and the pressure in the port is higher than the pressure in the crank case. At light throttle, it is a lot better to make the car a hybrid and simply shut the engine down for a while. This lets you use a smaller engine and also gets the engine to be always running more efficiently.

[@jasonhull1342]

In the 60s and 70s two Villiers engineers built an twingle/twin 500cc 2 stroke engine, that used the fuel and oil cooling of a 4 stroke ,but with no valves and a combustion stroke each time the piston hit TDC like 2 stroke. The engine was clean running and powerful, with around 20% cheaper to build than a 4 stroke engine. NVT built a running prototype in the mid 70s but lacked the money to put the bike into production.

[@fabbri4497]

Heavy stepped pistons...

[@completelyboringstuff204]

The hard part seems to be the intake- exhaust transition inside the cylinder, but I guess Mazda will take care of that. Sort of a similar idea (which turned out to be a combination of two-stroke Diesel and GDI gasoline engine) struck me almost 40 years ago, but never made the way from my head to the workbench so far...Thanks for introducing the concept!

[@hastuart9639]

This actually works in practice on Marine Diesels, so no reason it won't work scaled down. Common rail diesel injection systems have been around for a 100 years and possibly more and yet are reasonably new in the automotive world and came from Marine engines designed and manufactured by William Doxford of Sunderland in England. They were also Opposed piston with tthe top piston acting as an exhaut valve as well as adding power and balance to the crankshaft. Though I wouldn't advocate opposed piston diesels for automotive use. Car mechanics are completely confused now. With electronic common rail and variable valve timing, twin turbos it has opened up new designs plu the sensors and ECU's, so I can ee longevity of the diesel engine with a bit of money going into research and development. Just look how far we have come in the last 25 years.

[@jozefdkois]

I came up with the same design when I was 19 years old, preparing for a physics exam. My class mates at the time laughed me off saying that 4 strokes are more than 2 strokes , therefore 4 strokes are better. 😅

[@metricdeep8856]

lol. ...and after graduation, you see some of those guys at the same industry workplace....at the same starting pay. It's an insult.

[@extractorfan2143]

You imagined that scavenging system, is that what your saying?, by scavenging I mean the egr system, that's one advanced efi programme.

[@PRH123]

an 8 stroke would be really cool then... :)

[@ColdWindPhoenix84]

I've long felt that even though two stroke diesel engines have a narrow power band, they were well suited to hybrid drive trains as the CVT makes up for the limited rpm range and the hybrid harnesses as much of the energy dense diesel fuel. This seems like a great design idea that could also work for diesel fuel.

[@youridv]

problem is diesel is done for in the EU due to regulations on emissions. In the netherland there are almost zero new diesel passenger cars for sale

[@scotcoon1186]

Trouble is, they only make power at high rpm. The noise would be enough to keep manufacturers from using them. If you've never run an old Detroit, slam your hand in the door, then you'll be in the proper mindset to drive it.

[@chrishartley1210]

Although this engine is currently being developed to run on normal fuels, I wouldn't be surprised to see it being adapted to run on hydrogen. The 16:1 compression ratio would be ideal for hydrogen injection since it has a very high "octane" rating and doesn't suffer from knock problems.

[@We-Do-NOT-Consent-303]

Hydrogen is NOT a fuel. You can not mine elemental Hydrogen. And to create Hydrogen takes electricity, so you are actually ruining the efficiency of the system with conversion losses. Hydrogen is an inferior technology, that is why we don't use it. Plus storing Hydrogen is very dangerous. It needs to be kept under 5000psi pressure. And it leaks through every other material, because Hydrogen is the smallest atom. Hydrogen tanks are typically 4 times bigger then Gasoline tanks for the same amount of power. Do some research before you are promoting nonsense on line!

[@jttech44]

Hydrogen is a poor choice for a internal combustion engine. Poor storage capacity, and expensive to store and transport, and, when used in an engine, reacts with the metal parts making them brittle and failure prone. Not to mention your options for creating hydrogen are either fairly dirty (fracturing methane) or inefficient (electrolysis) so the whole idea of "only emitting water" is fairly dead on arrival. Not to mention the whole "the only emissions are water vapor" is false anyway, you still produce side products, and in an efficient hydrogen engine, you also produce nitric acid, because of the high temperatures. Basically, it's a meme fuel, you're much better off finding efficient ways to close the fuel cycle for normal hydrocarbon based fuels.

[@We-Do-NOT-Consent-303]

@@jttech44 All correct. Stupid people don't do any research they just parrot fake YT videos they have seen. We are using Fossil fuels because they are the best option. The problem is not the fuel as fare as pollution, and CO2 is NOT a pollutant. The problem are the cheap engines that burn dirty and does not last very long. We could make clean burning engines that last 10 Million miles. But we don't because there is no profit in that!

[@chrishartley1210]

@@jttech44 Unfortunately your comments are either hopelessly out-of-date or factually incorrect. I'll go through them one by one. Expensive transport and poor storage. Out-of-date. Hydrogen can now be generated at the refuelling point and compressed to energy densities comparable to diesel fuel. All that is needed is water and electricity. Hydrogen causes embrittlement in engines. Factually incorrect. Embrittlement occurs at much higher temperatures such as those used in welding. There is no reaction of this type at internal combustion engine temperatures. Hydrogen production is dirty or inefficient. Out-of-date and factually ambiguous. Hydrogen from methane is cleaner than burning fossil fuel to generate electricity for EVs. The by-products are captured so from that point of view it is 100% clean. Like the fossil fuel based electricity made for EVs that will be phased out over time as more point-of-sale hydrogen generators are built. Hydrogen from electrolysis is now more efficient than storage of power in batteries and will continue to improve. Hydrogen produces nitric acid. Factually incorrect. This is based on engines which were converted to run on hydrogen rather than designed to run on hydrogen. JCB, a major UK farm equipment manufacturer, have produced an engine of about the same size and power output of a diesel engine. Although it does produce some oxides of nitrogen, even without any filtering this is at about 3% of those produced from the most efficient diesel engines after filtering. With filtering the output is literally just water vapour. Why have they built this? Because at times agricultural vehicles (and others) need to run 24/7. Except for refuelling which A) takes place in minutes and B) can take place at the work site. Even with comparable charge times an EV still has to go the the recharge point. But the primary reason was the weight. Agricultural EVs will weigh 50% more than current or H2 ICE vehicles causing them to sink into soft farmland. Roadside refuelling stations for fossil fuels can typically refuel 12 to 20 vehicles at the same time. In order to service the same number of EVs at peak times that will have to increase to between 60 and 100 charge points for a charge level which probably won't even let users complete their journey. There are zero plans for this to happen. Look at the queues already at some of these charge stations. Dozens, soon to be hundreds of vehicles waiting for hours to get recharged. And that's now. Wait until it's a dark cold winter's night and your vehicle doesn't have the range to get you home. With no heat in the vehicle because the battery is empty. And the same is true for all the other poor souls waiting for their turn to get charged, there will be hundreds or even thousands in the same position. Coming soon to an EV near you. But hydrogen is a meme? OK, if you say so.

[@milojanis4901]

16:1 may be the mechanical compression ratio, but the dynamic/effective compression ratio is much less

[@SamMonkulas]

Very nice super clear video with all technicals double checked. Keep it up. 👍👍

[@repairman22]

Thank you.

[@TheNfurter]

@@repairman22 I think, he ment it ironic...🤔

[@kurtnelle]

Takes advantage of knocking! Turning a known weakness into a strength? Bravo Maza.

[@chrishedlund2688]

Interesting. There are actually a lot of improvements to the 'traditional' 2-stroke that are worth mentioning as they improve volumetric ratio (milage) and reduce oil consumption - these were developed in the 60's to '90's. Tuned exhaust pipes re-inject unburned charge from the exhaust back into the cylinder to be burned in the next combustion cycle - they can be tuned for variable engine rpm with 'sliding pipes' seen on some racing boats. Loop charging directs incoming charge to more efficiently displace exhaust on the upstroke, improving scavenging and reducing amount of unburned mixture escaping the exhaust port. Exhaust 'power valves' change the port geometry for better efficiency over a range of rpm's. Evinrude/Bombardier had some additional improvements that reduced oil consumption to a negligible level...they had less emissions than some 4-stroke outboards and were able to pass strict emission standards.

[@晴康太田-e1j]

構造上燃料にオイルを添加する必要無いンだけど(呆

[@arwzqu1964]

Its amazing what has been accomplished with the old piston engine over the last 40 years to make it powerful, reliable, efficient and relatively clean burning.

[@PeterJ-ij6mm]

The AFR of 14.7 : 1 is by "weight" and not by volume as stated.

[@gbone7581]

Mass

[@CanadianOnlooker]

I've been working on designing 2 direct injected 2 stroke supercharged for 2 years. The problem with overhead valves it traps exhaust at the bottom of the cylinder. This greatly reduces volumetric efficiency. The egr effect is good, but reduces efficiency just like typical egr systems. Then needing bigger motor to produce enough power to travel. The reason 2 strokes work is the placement of the intake & transfer ports being at the bottom when the piston is at bottom center. This can be modified to change rpm power output. Same as the intake windows in the piston. Just a piston change can make more low rpm power or high rpm for this reason. The other issue your using only 1 set of exhaust valves which means it has to spin at 2x the rpm as a normal cam would. Imo the best design is supercharger connected to bottom of cylinder, 2 exhaust cams alternating, & pistons with 2 sets of oil control rings to reduce oil at the intake window. A pcv system (& air oil separator) that can handle a small amount of boost which allows oil under small pressure into the piston when closed/ covered instead of oil going into the intake port. Some oil will be burned but not much more than typical car using oil (like Subaru).

[@stubby7934]

Been waiting for someone to put this in to production since direct injection started coming to gasoline engines. yay? Won't sound like a two stroke...it won't be in the middle of the power stroke when the exhaust port opens, won't get that "pop". I'm going with it sounding closer to a 4-stroke, high-revving motorcycle engine.

[@billmalec]

KTM makes two stroke bikes with fuel injection and oil injection for that matter and electric start...

[@benperkins2929]

@@billmalec so?

[@billmalec]

@@benperkins2929 so, you never stop learning or shouldn't be unwilling to.

[@a64738]

@@billmalec What do KTM making normal 2 stroke engines have to do with this ? (hint NOTHING !!!)....

[@cornishcat11]

@@billmalec and how does that apply to the sound? hint it does not

[@dudefuude7921]

Cool concept. For those of you doing the math at home: Your 2L engine is effectively a 4L engine if forced air at 15psi. With this, that 4L is now power equivalent to an 8L engine due to twice the power strokes. As an extra bonus, if the dead volume of the exhaust is oversized to allow mixing, the "belt driven compressor" (supercharger) and timing can be adjusted to mix extra fresh air into the exhaust stream at lower RPM, make the emissions look better (except the unused O2 would be high)

[@JohnDoe-bd5sz]

And particles. The higher compression makes particles just like diesel cars, this is why they now have to fit GPF's to petrol cars. The "Diesel cars are polluting way more" mantra has been shot to high heaven with these engines.

[@MaacAbra]

@@JohnDoe-bd5sz interesting!

[@battshytkrazy156]

FALSE. oversimplification

[@rabbitdrink]

you need a bigger turbo/super to make that 15psi though. cause you got 2x air going into the engine. but of course, you should put one on then

[@JosephCowen-ru7up]

The idea came from Ralph Starich an Australian engineer who developed the Starich Orbital Engine in the 1960/70s in his orbital engine the 9 sided rotor orbited like a planet sun relationship , it used this two stroke system of valves and a blower exactly like this is , it was installed in cars in the 1970s a Ford Cortina as Ford was involved , but the problem was sealing the vanes or orbital pockets , the rotor does not turn only orbits the crank, and the other problem was fuel injectors and pumps not being high pressure enough back then , computer engine control has now caught up , Mr Starich sold the patents to Ford who were working on a small two stroke triple engine in the 1990s , Mr Starich kept the patents on the direct injection / valve idea and sold them to Evenrude Outboard Motors who were developing a two stroke V6 with OETI orbital engine two-stroke injection but four strokes took over the market , I would say Mazda has recycled Mr Starich s patents and or bought them as this is exactly his original idea for the Orbital motor , fact is if working the Orbital Two-stroke would have changed cars for the better , the one in the Ford Cortina in the 1970s was only 14 inches in diameter, 4 inches thick and weighed 60 kg, had a power output of 221 HP and 267 foot pounds touque at 5500 rpm from 1.8 litres . That was a single rotor , he could have stacked them like the 13b or 20b Mazda Rotary's , this was good power back when V8S had about the same power from three times the displacement and 5 times the weight

[@davenorman8251]

True the Orbital 3 cylinder 2 stroke was supposed to debut in the 1991 model Ford Fiesta but it didn't happen ford also worked with lotus on a high performance version but that never went into production either..maybe Mazda will do it finally.

[@JosephCowen-ru7up]

@@davenorman8251 true I heard the same , yes maybe Mazda will

[@jancvdweide6646]

Maybe you didn't know this, but Mazda and Ford worked closely together and when they parted ways, Mazda took many of these things with them and further developed them with modern technologies.

[@johnschreiber1574]

Not sure about today, but I believe Ford owned as much as 25% of Mazda

[@jancvdweide6646]

@@johnschreiber1574 That is correct, but since I think 2015, Mazda is no longer part of Ford

[@65bug519]

this idea has been kicked around for many years ,Smokey Yunic had a high output version back in the 70s and Orbital technologies came out with small helicopter engines in the late 80s, BRP had a semi version of it in seadoos for a while as well.

[@robertmintz63]

Back in 1973, in Canada , I got to drive (for a couple miles) a Ford tandem axle gravel truck , while the owner rode with one of his junior drivers . He said it was oil injected 2 stoke gas & it sure had some power. I don’t remember if it was direct injected for the gas.

[@locker1325]

Hopefully it's not just another pie in the sky concept. But Mazda seems to be an innovator. Let's see if anything comes of it.

[@gregscott989]

Still got a crankshaft...puts a fundamental limit on the power that can be gained from each power stroke. If you think about it, the force vector generated by the power stroke is in the direction of the center of the crankshaft when the cylinder pressure is highest. Only the component of the vector that is tangent to crankshaft circle can do useful work. That only occurs very briefly in each crankshaft revolution.

[@Clyde-2055]

Have you ever heard of crankshaft offset ?? - done for the very reason you cite here.

[@WillDunlop-i3u]

Sorry for diverting the conversation a little, but It is interesting to realize that the piston "rotary radial" (different from "normal radial" piston engines) - had pistons, conrods and a crank, but were actually true rotaries, (the crank was stationaryl and was attached to the airframe, - the cylinders rotatated around it - so there were no actual reciprotaing parts (just "relative reciprocation") - there were some oscillating parts, like conrods - Main problem was "precession" caused by this rotating mass, it did tend to affect the aircraft when changing direction!! - perhaos it could be revisited as a potential generator?

[@JosephOlson-ld2td]

An Australian patent in 1980s used an AIR injector and a fuel injector, eliminating intake valve, allowing 2, 4 or 6 stroke variable cycle engine

[@kwahoo5746]

I remember this, the company implementing it (in Ford Fiesta IIRC) was called Orbital.

[@catoaarseth]

I have been thinking of a design like this for ever but never had the funds or machinery to try to build it 😑 but fun to see it 😁

[@ChunkyKong32]

Awesome that Mazda continues to innovate their combustion engine so well!

[@challacustica9049]

The problem is parasitic loss from the compressor. If they can use an electromagnetic clutch of some kind to switch to a turbo when exhaust gasses are built up, it will be much more efficient.

[@GIGABACHI]

Like a shrunken system like the one used on EMD big diesel engines. It drives the turbo mechanically of the crank until enough exhaust gases are generated to spin the turbo faster than the crank can.

[@challacustica9049]

@@GIGABACHI yes exactly, like that.

[@tturi2]

you still need lower exhaust pressure than intake pressure as the intake and exhaust are open at the same time, more than just overlap

[@millennialpoes5674]

Parasitic losses are inherent with any forced induction engine. Not just this one. The losses are more than compensated by the additional power the blower provides. Hence overall efficiency increases.

[@millennialpoes5674]

A turbo would also put additional back pressure on the exhaust stream which is a disaster for a 2-stroke. So no that's a terrible idea.

[@Bitdog4U]

Thanks, that was a good presentation. My version of a 2 cycle motor was: two eccentrics on a crank for two connecting rods in apposing horizontal cylinders that fire at the same time eliminating the need for Babbitt bearings, so it can use roller bearings to reduce friction.(increase roller length for extra strength). A large third cylinder going up that compressed & cooled intake air. Then one injector by one large intake valve & 2 spark plugs per cylinder. Exhaust port was at bottom of piston stroke as a normal 2 cycle has. Over head cam was gear driven using an aluminum hub & spokes with a steel tooth ring. Add idler gears to reduce gear diameter if needed. For bigger engines add cylinders in pairs. Crank case has a normal 4 stroke gear driven oil sump pump. Air cooling fins every where with water cooled heads. A 4 cylinder motor would have 2 vertical intake cylinders one piston going up as the other goes down, & separate crank cases would not be needed. I wonder if a rubber diaphragm would hold up. Magneto spark system has magnets mounted on crank case plate and the 2 coils go around, so apposing force Eddie current magnets don't electric brake fuel efficiency and the coils spark just jumps a gap like a distributor cap does. Spark advance just turns the plate the magnets are on. To get power at a very low RPM we fire after TDC. I give my idea to the world, you can make it, use it, sell it, but not own it, cuzs it's my intellectual property. 11-25-2023. Invention 743 is a magnet on a springie flat bar with a coil on each side + 4 diodes. Mounted on the VIBRATING heads, the magnets get going by the coils which produces electricity 4free. A bunch of them in a row with a cover is a power bar.

[@Bitdog4U]

I forgot to add that the idea is to make an engine efficient like a bicycle, which has limited power. A real man can produce 1/3 horse power or so, yet can do 40 mph on a bicycle. A Honda 50 sport is 5 horse and does 60. It seems all motors just add larger cylinders to compensate for wasted power at a fuel efficiency cost. So my design has 2 cylinders firing at the same time, one pushes on crank above the main bearings and the other the below so they counter each other so mains don't need to be difficult to turn babbit bearings designed for maximum pressure, cuz there is no pressure. Then the crank can be flat plates on a main shaft to hold the connecting rods so that internal wind resistance is smaller. Electric breaking with spinning magnets next to metal that conducts electricity can loose more power than people understand. Take a motor out of a direct drive washing machine, short the output wires and try to turn it. You can't turn it at all. It is electric braked to a complete stop, or very very close. I forgot to add that a turbo charger could be the fix for 2 cycle stuff. When the exhaust port vents,the fan blades get a blast and as the pressure decreases the blades could cause a needed suction using the fly wheel effect. Then the intake air pressure buildup it creates on the other side can puff into the cylinder as the valve opens pushing out more exhaust. A turbo charger would eliminate the need for a vertical piston pumping intake air. Fuel injects as the exhaust port closes and you avoid fuel waste. The oil in the crank case eliminates many normal 2 cycle problems like mixing fuel+lube & pollution. Hot oil can be used for heating the cab which cools the motor. Also the Peltier Seebeck effect modules can produce electricity from it's heat as it heats the cab. A thin plastic type solar panel on the van's roof could help eliminate the need for a standard alternator, which uses electricity it produces to make the spinning magnet that produces the electricity. It's an E-brake waster. The vibrating magnet on a flat bar producing electricity thing could be on the suspension also. And once I got a speaker magnet a spinning like a donut on a string and held a degauzing coil off a tube TV up to it and it produced more electricity than any other magnet coil combo that I ever messed with by a lot. The coil was 8" diameter small magnetic wire is all. So if multi coils surrounded a spinning cheepo magnet in a plastic housing you would have an efficient alternator that could be engaged when needed? I like cast steel/iron cylinder sleeves myself. A standard cam & a pull rod design might be the right route to go if valves floating could be avoided. Could the design burn diesel, or waste veggie oil ? Avoid copper in the fuel system and it would burn WVO without the self destruct part ? WVO eats copper with a green crust buildup crap causing all connections to leak over time. Envision X-engine in a longer narrow low mini van designed for low wind resistance, burning WVO on the freeway with 8 passengers in a taxi cab going from the airport to small towns. Americans buy bigger trucks every year with beds so high you can't load anything in it. Stupid is as stupid does. I had a free 3/4 ton Nissan SE-V6 once & it was great. Any way, there is something to ponder.

[@Johnsmith-zi9pu]

Now that some insurance companies have started refusing to insure electric cars and ferries refusing to allow then on board, the combustion engine has a bright future. The current battery technology is totally unsuitable for cars.

[@user-gf3mu5uc8j]

Detroit diesel has been using using valves in their 2 stroke diesels for decades. Exhaust valves but still valves in a 2 stroke none the less.

[@drlegendre]

7:10 "One spark per RPM." One spark per revolution.

[@Clyde-2055]

One ignition event per cylinder per revolution.

[@PrecisionClays]

@@Clyde-2055 one ignition event per cylinder stroke... :)

[@ethansilva4228]

Dude, a 4 stroke 2 stroke hybrid, this is legit. Thanks for explaining every single type of automotive engineering.

[@DigBipper188]

There is a pretty big downside to the idea of valving a 2-stroke like this, and that's valve float with larger displacements. If we take a normal, say, 500cc single cylinder 4-stroke engine, its valvetrain speed is timed in a 2:1 ratio referenced to the crankshaft. So for every turn of the crank, you get half a turn of the cams. If your 500cc engine started experiencing valve float (where the valves are incapable of closing in time due to their inertia) at, say, 9,000 RPM, then using a similarly sized and spec'd valvetrain on a 2-stroke variant of that same displacement engine would half your peak engine RPM and you would be restricted to keeping the engine below 4,500 RPM. This might not be so bad if you tune the engine for peak efficiency close to this range or the engine has a high torque output, but if it's a small over-square engine that needs high piston speed to produce power then this is going to become a major problem if you want any degree if power from the engine. That said, Formula 1 could be a strong starting point for where to get a valvetrain that can be spun at those speeds. Most F1 engines can spin over at 20,000 RPM meaning their valvetrains can take 10,000 RPM without experiencing valve float no problems whatsoever. If we're able to affordably implement the air spring system that they have in these engines then that would go a ways to making an engine that can rev high, produce good power and not shred itself to pieces. The other alternative would be Koeniggsegg's FreeValve system, since that uses an electromagnet to control the valves, eliminating the camshaft. You can also electronically control the valve timing, duration and lift with this technology, which means you can potentially reduce the chances of valve float ruining the engine by reducing the valve lift at higher RPMs. This could potentially even be cheaper than the F1 air spring systems, as they also don't require sodium filled valves, you get rid of a load of air springs, you ditch the cam shaft, bearings, pulleys / chains and all you need to replace it with is a series of electromagnets and a sensor wheel that detects the engine RPM and timing.

[@MarcusLindblomSonestedt78]

FYI, the 20k+ F1 engines used pneumatic valve springs, not sure about current 12-14k engines. Might work since we have compressor already, but might be cranky (:-p) at startup. :D

[@MarcMonson]

why not keep the cam spinning at half the speed as the crank but have to lift profiles on both cams 180 degrees apart?

[@DigBipper188]

@@MarcMonson You'll still run into the same issue because the float doesn't occur as a result of cam speed. Your valves have inertia (in ELI5 terms - that's resistance to being moved and changing direction - It's the same force that slams you into the back of your seat when you accelerate hard in a car, or stops silverware escaping the tablecloth if you can rip said tablecloth from beneath the silverware fast enough). This inertia increases the faster you try to move the valve in the head right until the point the valve's inertia is enough to overcome the spring's closing force and the valve hangs itself open for slightly longer than it's supposed to be. The valve momentarily stops following the profile of the cam lobe during a float, so reducing the cam speed and adding an extra lobe won't do a lot to solve this. It's still gonna be pushed 4500 times a second and float from the raw speed of which it's being opened and closed. In minor cases (e.g in a non-interference engine, where the valves and piston don't occupy the same regions of the combustion chamber) this would be noticeable as a roll-off in power at high RPM or breaking up / stuttering. In the worst cases (e.g an interference engine, where the valves and piston occupy the same regions in the combustion chamber), this can lead to the piston smacking into the valves, either bending them and causing the engine to run rough, or if you're super unlucky they will snap and cause some major carnage in the cylinder.

[@DigBipper188]

@@MarcusLindblomSonestedt78 Precisely what I was referencing. The older F1 V10s used sodium filled valves for improved cooling and pneumatic springs to cut down on weight and also prevent resonance in the valvetrain building up and causing valve float. Not super cheap to implement but the glorious roar of those engines while being ripped flat-out down a straight is all the info we need to know about how well it worked! :)

[@life_of_riley88]

Not a problem, you'll just need ramp angle modifications on the lobes vs a 4 stroke coupled with higher spring rates. A 5000 rpm redline on this engine would produce *double* the amount of power pulses vs a 4 stroke at 10,000 rpm🤯

[@darausus8315]

Rise of electric cars will not end petroleum and gas engines. These engines would just become inbuild generators. And that where they would shine - generators could always work at max efficiency.

[@IANHANDS]

Hybrid EV

[@myMotoring]

I think Mazda will produce 2 cylinder version for the mass market since the power phase is similar to the 4-pot 4 stroke.

[@kimmer6]

45 years ago in Engineering school I was looking to build a valved 2 stroke engine as a Senior Project. The limitations were staggering. Now, variable valve timing is employed in plenty of production engines and direct injection is pretty well developed and in use. It looks like Mazda is on the right track. So many things are now possible and I hope that this design will further fuel efficiency and reduce emissions.

[@manin10]

Always thought this design would be ideal for a hybrid car!

[@b226tj]

So it’s a 4stroke that thinks it’s a diesel 2stroke, but it’s actually a gasoline engine? WEIRD. I want one.

[@trapperjohn3400]

I had an idea similar to this but with a V layout, where one cylinder uses reed valves for the intake, and acts as the air compressor for the next cylinder.

[@jareknowak8712]

Same here.

[@jw-hy5nq]

That has been done, can't remember what it was called but Mazda and Volvo had the engine on the drawing boards in the 70's or 80's. Each piston pair consisted of a normal 4 stroke cylinder and a larger paired one that was larger. I don't think it went anywhere because the "pump" piston was always cold leading to oil pumping past the rings and you basically doubled friction losses and reciprocating mass. Wasn't worth the complexity. This is similar to the five stroke engine where the exhaust from 1 cyl is fed to another to scavenge more energy.

[@WillDunlop-i3u]

@@jw-hy5nq .......... This principle was used by Ricardo? ( the "Dolphin" engine was used (successfully) in the early 20th century, also by some other manufacturers - Trojan delivery vechicles having used it successfully till just after WW2.

[@aceais6613]

2stroke collab with 4stroke + diesel = too good to be true 🤤

[@Justgaragenit]

This is really cool how they integrated so many types or systems into 1 ,seems like it may be a night mare to repair or diagnose. Really curious to see how it works in a real life scenario as well as longevity.

[@youridv]

why would it be a nightmare to repair? It consists of the exact same parts as a regular 4 stroke supercharged engine and has no additional mechanical complexity. It's arguably simpler than modern turbo 4 cilinders because it doesn't have a waste gate or even a turbine.

[@Justgaragenit]

Not so much a nightmare. Would definitely be more difficult to diagnose, considering it has characteristics of both gas and diesel engine as well as 2 and 4 stroke. Compression and spark ignition.

[@GeorgeJefferson-h7w]

I like it. That was the clearest and simplest explanation of a standard ported two stoke I think I've ever heard. That new one seems kind of crazy, but we'll see.

[@daledavies2334]

Actually the exhaust port(s) is uncovered a couple of crankshaft degrees before the transfer port to allow cylinder blowdown. Otherwise the residual pressure in the cylinder would further pressurize the crankcase and possibly ignite the intake charge.

[@sketchypoodle1236]

Thank you. It's nice to have at least one qualified response. Same thing in the Detroit diesel, the exhaust valves open just *before* the piston goes below the intake ports to let the majority of the combustion pressure start moving out the top of the cylinder before intake charging. Port timing in a two stroke is everything.

[@budstep7361]

This is so cool! Mazda not giving up on innovation in combustion is so awesome, quite the feat of engineering!!!

[@TwoHemiViewer]

Don't forget electric cars are remote combustion vehicles. Remote meaning getting electricity from combustion power station.

[@572Btriode]

Not to forget either that a great number of them are thus coal powered. . . . . . . . . . . . .

[@dnomyarnostaw]

​@572Btriode Not to forget that they are STILL more efficient than Diesel because the Coal Stations are close to 90% thermal efficiency due to higher temperatures. Even if all EV power was coal originated, it surpasses Diesel for efficiency as well as keeping dangerous particulates out of high population areas.

[@572Btriode]

@@dnomyarnostaw Indeed so, but you do have to factor in both the transmission losses to get electrical energy to the vehicle socket and the energy/pollution budget of getting the coal out of the ground and into a power station. The electric vehicle has the penalty of carrying the significant battery "ballast" around with it, sadly at the moment batteries do not have a very good power density compared to liquid fuels. IIRC, two UK universities have separately made very detailed studies of the energy and pollution budgets to produce electric cars and the near identical IC powered variants. It transpires that the budgets are equal at between 80,000 and 100,000 miles of use with the EV then being superior. Provided you do not need to replace the battery.

[@yolo_burrito]

@@572Btriode the US generates more renewable electricity than coal powered. www.eia.gov/tools/faqs/faq.php?id=427&t=3

[@yolo_burrito]

Not all of it. Over 20% is not generated by combustion. www.eia.gov/tools/faqs/faq.php?id=427&t=3

[@hinzeyo1643]

Man, gotta love Mazda for thinking outside of the box time and time again.🤯

[@Fisherman4200]

I think fist valved 2 strokes are now 100 years old

[@djhrjeiwhri]

Wtih Compression ignited and ditect injected?

[@IrishSpyHD60]

Old ideas often only failed because of technological limitations of their time. I think almost every old forgotten engine format should be revisited again and again just to make sure we don't miss out on something!

[@clevernduruza8624]

@@djhrjeiwhri most people rush to comment without watching the whole video

[@htimsid]

So true.@@clevernduruza8624

[@TSAR2010]

@@IrishSpyHD60Fairbanks Morse never failed

[@davidbutcher1105]

The EMD 710 engines are 2 stroke diesel engines that use a one way clutch driven turbo. They act as a blower at low RPM/HP requirements but once the exhaust gasses get hot enough the turbine over comes the clutch and functions like a regular turbocharger.

[@petehalasz7547]

Great research and video.. being a licensed technician for almost 50 years and I've always said the 2 most efficient ICE have been either the rotary or 2 stroke.. this is absolutely brilliant and should change the ICE if it goes into production.. i hope they stick to it...

[@matthewshambler2644]

In a hybrid and EV obsessed world, I respect Mazda’s commitment to the internal combustion engine.

[@jakubnedoma9089]

It's funny enough to see one sample video from the Czech Republic (white V8 BMW) and the other from Argentina or something ... but the second clip showed a JAWA 350 - a historic motorcycle made in the Czech Republic (then Czechoslovakia) and fairly nice one :D That JAWA is also two-stroke btw ...

[@apperition47]

Detroit Diesel has had this from the begining on thier engines.

[@a64738]

Detroit diesels have ports for the exhaust, not valves, big difference... Only thing that is same is the need for a blower for the exhaust scavenging.

[@davidbrayshaw3529]

Valves for the exhaust, cylinder ports for the intake. @@a64738

[@558vulcanxh]

My dream engine for car has always been a 3 cyl 2 stroke diesel ⛽️ and we may eventually get one 😊

[@irvinstruckinggroupse]

The 2-stroke engine, but with a 4-stroke twist

[@Wingnut353]

Aka it's retarded. Seriously though this engine stops short of actually being good, to get there we need a 2 stroke opposed piston engine that eliminates the complicated head.

[@reneverstraeten]

Fuel efficiency is the target. If a car with a combustion engine gives a 50% "Carnot" efficiency from fuel to movement, it is way more fuel efficient than an electric car overall. An electric car has to amortize its way higher use of energy in the production of the car while in use of alternative fuels, overuse of metals and electronics, but especially the high energy use for making the battery. When an E-car is filled with power from coal or gas plants, the electric power is on average produced with 35-45% efficiency, although a natural gas power plant can have an efficiency as high as 61% (these cannot be used in a fluctuating power grid dictated by solar and wind). To drive on solar and wind sounds practicable, but do you want to stop driving when there is no solar or wind? Was the energy break off, like the first 200,000 km with an E-car is to compensate for its high energy consumption in producing them before it becomes more energy efficient than a combustion car? With these new types of motors, the advantage of the combustion car shifts even more towards this proven technology, away from electricity. Apart from the disadvantages that E-cars have in reach, fast fueling, bad cold weather, limited acceleration, air-conditioning, and limited energy storage. The future of cars will be combustion, perhaps in combination with synthetic diesel or gasoline made by nuclear power after cheap fluid fossil carburants run out.

[@ianjones7740]

Do I think it will delay the arrival of electric cars ? I sincerely hope so !

[@cosmovg9955]

The design definitely seems like it works but im sceptical of the reliability cuz air needs to be forced into while the piston is undergoing compression so you need high boost but also need more precise tolerance i guess

[@Eduardo_Espinoza]

& super chargers have high parasitic losses, I'm not sure if Mazda chose a roots types blower like in the animation but it doesn't help for gains stand point. Optimistically, they can put an electric center fugal super charger/turbo for that, turbos have gone a long since. Maybe they can do a bi turbo setup like the recent 2024 production i4 diesel sprinter van from Mercedes. 🙂

[@Wingnut353]

this is a problem detroit diesels solved like 90 years ago... also you can bypass the blower essentially free wheeling it once turbo pressure is high enough when the engine is under load.

[@AtariFTW]

Henry Ford almost used this design in the early 1900's except without the blower.

[@jamesbosworth4191]

Probably couldn't get it to run well enough for it to be usable.

[@cornishcat11]

it would not work without a blower@@jamesbosworth4191

[@3RTracing]

lets be very clear on who developed the 2 stroke engine with valves and made it the most commonly used power plant system throughout the world and promised delivery any where in the world for any part in 24 hours or less. It was the Electro Motive Division of General Motors. Their 2 stroke diesel engines were and still are an industry standard that has NEVER been surpassed. Some locomotives?? How about the majority of locomotives built around the world since the late 1930's. And thousands of them are still running every day with EMD Diesel engines, as well as boats, trucks, stationary power plants and oil rig equipment. EMD diesels can run on diesel or NG, or LPG. They are indestructible and very easy to repair and service. And they use a gear driven supercharge system instead of belts and chains. Some of the more sophisticated EMD engines use a combination of driven superchargers and turbochargers to further increase the efficiency. REGARDLESS there is very little difference at all between the MAZDA 2 stroke with cams and valves, and the EMD diesel that operates on the exact same principles. However the EMD 2 cycle systems were started way back in the early 20th century by Winton Diesel who became Detroit Diesel. Do better research and home work, your video is full of errors. But I am glad this very well seasoned technology is being revived and utilized in a different application: consumer vehicles. Thanks

[@kiwijonowilson]

Its a good idea but no doubt you lose some efficiency driving the super charger (which is more than pumping losses of a conventional 2 stroke). Of course having a smaller capacity engine should help with fuel efficiency so will be interesting to see what fuel efficiency ends up like. As far "Do I think it will delay the arrival of electric cars ?", I think the answer is not significantly as I think that the horse has already bolted (in a lot of countries EV sales already outweigh ICE sales), but maybe it will help Mazda hang in there.

[@doost6233]

The idea is to have something does not smoke and does not pollut the environment does not matter if it is two strokes or four.

[@takemebacktothen]

mazda has a thing for inefficient engine designs

[@mattt198654321]

Congratulations, they invented Detroit Diesel XD

[@leighchamberlain25]

So that's a combination of two-stroke and Miller cycle that uses dieseling and EGR.... DAMN!!! Go Mazda

[@andrewludlam2565]

I used to work on Detroit Diesel engines back in the 80s, the V16 had 4 valves per cyl, superchargers and two turbos, the injectors were also rocker operatedi , imagine setting the tappets😕

[@gordennyabunze2853]

The variable timing of exhaust valve with engine load is genius

[@johnschreiber1574]

Yama exup

[@KerbalFacile]

Clever ! Split the first two steps from the last two of regular 4-step cycle by keeping them on separate sides of the piston.

[@rasmus1600]

Correction, most big ships use a turbo, not a super charger. Even the ship Madid Mærsk you show, use 2 MAN 8S80ME C9 engines that are both turbo charged. Even some other of the videos there's a turbo charger. Compressors work at low RPM, yes in cars, where idle is like 800 RPM. But a ship where max RPM is at insane 80 RPM, it makes up with the insane cylinder volume, where a person can stand inside the cylinder. The turbo only spins at 2000RPM and there's most likely several turbos.

[@repairman22]

Yes. Its true. I Was referring to cars when describing 2 stroke diesel. Ships have space for auxiliary starting compressors. Today cars can have electric turbos.

[@DailyLifeSolution]

You explain the engines the best.

[@stevem3akm]

Just to show very little is new, I am currently rebuilding a 1924 Tatra t12 Rennwagen engine which is air cooled flat twin with poppet valves, it used to have 3 valve heads and roller bearing crank. The camshaft was mounted on the nose of the crankshaft so turning at engine speed. Built like this it virtually doubled its horsepower.

[@kurtminges647]

I don't know I only watched it once I'm kind of high but couldn't they use electric solenoids to control those valves,,, wire it to the crankshaft positioning sensor it'd be easier to adjust the valve timing than mechanically,, no camshaft lighten the load 10 lbs ,one less thing to oil...... and what about the Achilles engine they can incorporate this system

[@The_sinner_Jim_Whitney]

Man, an I4 with a cross-plane crank (Like a Yamah R1) that worked like this would sound RIDICULOUS... I bet it would make all kinds of power, too. Awesome.

[@howebrad4601]

Excellent idea especially leaving part of the exhaust gasses in place to bump compression and maximize energy pulled from.each drop of fuel

[@nigelcairns6203]

With that exhaust note in will be everyone's favorite.

[@Kneedragon1962]

Now, amongst your viewers, there would be a few Australians. Who has heard of Harrop's Howler? In the late '50s & early '60s, a young man called Ron Harrop started drag-racing an FJ Holden. It had the original Holden inline 6, but it had a blower on the side. Full steel body, big heavy car and a small (161 cube?) engine ... Thing is, it didn't SOUND anything like a Holden 6. It sounded like it was turning 11 ~ 12 ~ 13 thousand rpm. Now I worked out in the 1980s what the 'secret' of Harrop's Howler was, but it seems Mazda has worked it out too. You can turn a 4 stroke engine, into a 2 stroke engine, if you have a roots style blower. Getting the thing to run, not that hard. Getting it to deliver big power, that's harder but it can be done. Getting it to run smoothly and reliably and efficiently and to idle and deal with normal traffic and things, that's hard. That's where modern electronics and fuel injection and stuff come in. But just for the record, three or four years before I was born, Ron Harrop was racing a stock body FJ Holden in Australia, that ran the original Holden 161 inch (? 149 inch? If you say so.) inline 6, and it ran like this.

[@sailincat2822]

Excellent video, very easy to visualize and understand the basic concept.

[@nickybritain3661]

I can’t imagine why you would need valves in a 2 stroke engine. As a young lad, many many years ago, I often ran a Villiers 8 E engine to such high revs it would internally combust and then took a few seconds to reconfigure itself back into a 2 stroke! Way more power that an equivalent 4 stroke of the same cc’s.

[@rre9121]

Thats really clever. Using exhaust gas scavenging to essentially reduce the effective displacement, but retain a large expansion ratio.

[@MilkshaketheKitten]

it's nice to see a manufacturer come up with some innovative ideas. To keep the internal combustion engine alive.

[@Dinolobe376]

An egr allowing for more compression and power ? How do you get more power from a gas that doesn’t burn ? Egr reduces emissions by lowering combustion temperatures so less NOx are produced. That doesn’t provide any additional power

[@repairman22]

This egr system only works at low load. has no cooler. it is similiar but not the same as in diesel. It is well explained in the video.

[@rorykennedy1125]

I hope it sounds like a rotary. Best sounding engine, after a non german 10v. It's funny how Mazda seem to be the only car company that haven't swollowed the 'anti life propaganda' pill.

[@scotcoon1186]

The supercharger on the Detroit was to keep the air moving through in the right direction. We had a 6v92t, the supercharger drive broke, smoke started moving in and out of the air cleaners and exhaust, and it wouldn't rev. Little 5" long shaft that broke was about impossible to find already in the late 90s.

[@jandevries3252]

I'm really looking forward to the emission details. Higher temperatures will cause development of nitrous oxides, minimal fresh air improves the risk of reaction into carbon monoxide...

[@colvinator1611]

Excellent graphics and presentation. Most interesting. Thanks a lot, Colin UK.

[@eugeneleroux1842]

It is always nice to see some metrics when a new concept engine is proposed.

[@plantfeeder6677]

On a piston ported 2-stroke engine you certainly can change the position of the ports. By raising or lower them through machining you can affect performance radically. In racing we called it quick-timing. This has been known since the 1950s but since most of you grew up with the two-stroke engine being banned, it's akin to NASA not being able to do something they did in 1969.

[@timkirkpatrick9155]

About time.The design is decades old.

[@joshgessinger4509]

Pretty exciting stuff im a 2 stroke fanatic been riding dirt bikes ATV’s and snowmobiles for 40 years im 44 now. Also raced bikes and pro snowmobiles for 15 years. The 2 stroke is lite powerful very simple to work on. This new mazda motor might be a little more sophisticated than a piston port or reed rage 2 stroke. Still very cool should make great power for its size and get great fuel economy. Could be the future instead of EV’s wouldn’t that be cool. Great stuff thanks for sharing

[@iankitney3460]

The sheer ingenuity of the human race never ceases to amaze me. In a lifetime of messing with engines I'm gobsmacked by this one.