Why There Aren't More 2-Stroke Cars

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Gasoline, diesel, rotary, and even jet engines we have today evolved from designs that are over 100 years old. With the push in EV tech of late, it’s tempting to think the advancement of internal combustion has run its course. But engineers never stop inventing, and a brand new design called the entry-ignition engine could change the combustion game. And it’s a 2-stroke! But can a 2 stroke engine hold off the EV rush? Let’s find out!
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[@brapinator8500]

honestly huge HUGE shoutout the the editors/animators y’all are under appreciated goats

[@jrngln]

All of that trash coming from a guy who promotes a company that uses murdered babies in their products❗️

[@holeshotshane5692]

Yeah especially with that Brayton cycle engine. That thing would've been hella more difficult to explain without a visual guide

[@fishstickslyer925]

Under rated 😂 they have 7 million subscribers

[@brapinator8500]

@@fishstickslyer925 the editors are underrated bozo

[@relaxationmusic9335]

No like rs s/o to them very much unappreciated

[@AgentJayZ]

Just a minor detail... in the lower right at 7 seconds in, that's the engine I work on in my shop. The Orenda turbojet was designed and manufactured in Canada. Its American counterpart is the GE J47. Both of these engines were used in the F-86 Sabre jet.

[@PorkChopForLifeMC]

sick

[@purwantiallan5089]

@@PorkChopForLifeMC sick as V8?

[@slowfudgeballs9517]

@diana p Do these actually make any money? They must trick someone because why else do they still exist.

[@JasonLuther1]

@@slowfudgeballs9517 Zero overhead, they can fish for free

[@evergreenrider]

@@purwantiallan5089 sick as piss bro

[@TheGearhead222]

I think that it was mainly emissions that killed 2 stroke cars. A buddy of mine brought his Trabant over from EG and drove it on IH-35 regularly. Many microcars also used 2 strokes and these , along with scooters, helped get Europe back on the road post WWII. Almost forgot, but SAAB used a three cylinder 2 stroke inline design for many years in their earlier models-John in Texas

[@anvilsvs]

That and fuel consumption. Two things which are somewhat related.

[@RailsofForney]

Amogus

[@EddieEducation]

This engine even borrows from ship steam engines from the 19th century - the big final cylinder is like a triple expansion! Love it!

[@thorodinson3597]

The triple expansion is also still seen in some modern Arctic/Antarctic ships powered by gas turbines. The turbine is essentially the first chamber, and then they have 2 more exhaust "stages" before the outlet, to extract every btu possible from the fuel.

[@tomxiong3630]

Could totally do this with a rotary. Utilize the first rotor for precompression and the second rotor for combustion. It solves the issue of the rotary's current issue of a hot side and cold side per rotor. Rather than having a hot and cold side, you could have a cold compression rotor and a hot combustion rotor. Basically a high rpm gas turbine engine except with rotors vs fan blades. This makes so much sense for the rotary since it can hit high rpm and recent rotary research encourages high rpm low weight rotaries that use the centrifugal forces to hold apex seals in place. Since the rotaries are stacked too, you can literally just pass the air from one rotor to another rotor all internal to the engine rather than using auxiliary piping. This is big money. Could finally make the rotary what it was meant to be. Very little moving parts, long-lasting, a ton of horsepower in a small package like a gas turbine, while also having the throttle response of a piston engine. Make this happen Mazda! Edit: Researched this design concept more and came out with an even better concept! Rather than even use rotor 2 for combustion, remove combustion from rotor 2 and separate this into a combustion chamber that sits in between rotors 1 & 2. Rotor 1 acts as a compressor, a giant rotor feeding extremely compressed air into the combustion chamber which is a constantly lit flame front. The chamber has a fuel injector and a spark plug and its job is to mix and ignite the fuel. However, once the spark plug lights the first flame, the flame stays on until the engine is turned off. As rotor 1 pumps air into the chamber, the gas/fuel ignites, expands, and enters into rotor 2. Rotor 2 extracts all this expanded gas energy from the combustion and drives rotor 1 via eccentric shaft. Coolant is focused all around the combustion chamber eliminating the water seal that constantly fails in the RX-8. The rotary will compress air and extract exhaust gas energy on both banks of each rotor one after the other which results in compression and power at every 180 degrees of crank rotation. Almost all expansion energy is extracted in rotor 2 because all fuel is completely burnt after the combustion chamber except in rich conditions. Holy crap this would maximize efficiency! 100% fuel burnt after combustion assuming 14.7:1 AFR and then it enters rotor 2. If Rotor 2 is optimized to extract exhaust gas energy then it would be one of the most efficient and compact engines ever. The design would only require 2 rotors/housings, a center section with 2 combustion chambers, 2 fuel injectors, 2 spark plugs, and a single eccentric shaft. All that is left is coolant routing and oil routing! Also since combustion is a constant pulsing flame, wear and tear are greatly reduced, this allows for extremely light rotors for very high rpm and greatly increases engine longevity. Definitely would last over 150k miles or even more! Will also sound like a giant pulsing turbo. Someone needs to make this! If nobody makes this I might go and make it. Comment what you would call it, I'm thinking maybe "Rotorbine" Eh...

[@Cher007]

Would love to see a concept on this!!

[@midlifehemi88]

I could be wrong, but I think back in the 30s or 40s, Rolls Royce was experimenting with rotary designs for military use, and came up with a diesel 4 rotor that worked like this

[@inaNis_]

The rolls Royce diesel rotary was basically the same concept, 4 rotor with two big and two small, the two big were pre compression rotors and the two small were combustion’s rotors

[@midlifehemi88]

@@inaNis_ yeah that's what I thought. Really cool and honestly pretty smart

[@tomxiong3630]

@@midlifehemi88 Oh wow, engineering explained actually made a video on this Rolls Royce concept. The damn thing made 350 hp @ 4500 rpm with the same power and way less weight than a comparable V8. This was in the 1970s. Imagine if we made one today that pushed rpm to 10,000 so it was reliable with centrifugal forces holding the apex seals and was used as a high rpm performance engine than the high torque low rpm designs Rolls Royce probably preferred. It is unknown why it died before production, most likely politics at Rolls Royce. Edit: Now it makes sense why they killed it. Low rpm rotaries would result in apex seals that chatter and break. Rolls Royce was probably unable to solve the issue of apex seal failure since they were using the rotary at such low rpm. Back to the topic though: However, the Rolls Royce design is very different from Entry Ignition. The Rolls Royce version utilizes compression to ignite diesel fuel by dual compression of diesel fuel by 2 rotors. Instead, my design uses the Brayton cycle which will pass compressed air from rotor 1 into the constant spinning flame front inside rotor 2 to generate power, hence the name Entry Ignition (Air from Rotor 1 enters Rotor 2 for ignition). Technically this already happens with regular Mazda Rotaries cause we always get Entry Ignition when the rotary dumps fuel and air which ignites as it enters the exhaust. They just let all this energy go to waste cause they dump it out of the exhaust pipe as flames. Also probably why they get such crap emissions. If they can pick this tech up, it would solve their emissions problem, their problem with a hot and cold side of each rotor causing failure, and increase horsepower output. Boom, just fixed Mazda's engine innovation plan for the next 10 years. Pick it up Mazda! It's big money! Link for Rolls Royce design: kzbin.info/www/bejne/Z6Gnm6qXprpjmrc&ab_channel=EngineeringExplained

[@Christopher_TG]

Sounds like there could be a lot of parasitic power loss with this engine design. You have 4 cylinders with 4 pistons being moved by the crank shaft, yet only 1.5 of them is actually generating power.

[@NickVetter]

The whole point is that instead of wasting power, the extra cylinders help recover more power. But the friction probably cuts that gain a ton.

[@Znarffi]

Yep. Engine balancing and friction will make the engine lean more towards a bad idea than a good idea.

[@DeadpanPear]

@@NickVetter That and why don't you just use a turbo to recover that power, and how is this engine not fucked already from the extra rotating and reciprocating mass. How is the engine not tripply fucked from having one piston constantly producing a ton of heat.

[@joshmnky]

@@DeadpanPear Yeah, it seems like you could replace the first and last cylinder with a turbo. The only problem is the turbo probably won't work at low rpm.

[@Appletank8]

@@joshmnky This kinda sounds like turbo-compounding, in which the exhaust turbo is actually geared to the crankshaft. Or you could just make it an electric assisted turbocharger for low rpm.

[@siamsasean]

That "getting you pumped about engineering" bit absolutely hooked me into hitting Subscribe. Not just your enthusiasm, but all the supercool info. As I understand it, the EI engine makes power from the large exhaust cylinder as the small combustion cylinder is on the return stroke. Letting the engine scavenge otherwise wasted power, and in my opinion, making it a ONE-STROKE engine. :-)

[@xavieroftheeast]

12:20 Germany is absolutely dominating this video

[@waclosh]

My father told me stories of my grandfather meticulously revving the 2stroke engine of his Trabant before longer descents to oil up the engine for prolonged engine braking.

[@julianbrelsford]

There's a KZbin video (Doug Demuro I think) where the guy reviewing a Trabant gets strict instructions from the car owner to just avoid engine braking altogether. The driver just put the engine in neutral and used the brake pedal to safely drive downhill.

[@wildman510]

That could probably mpwork, I've heard also that if you pump the throttle periodically it'll stay oiled

[@nolanbennett6617]

@@wildman510 more than pump the throttle, I would say a steady slight hold, being mostly on the throttle more than not. i race motocross and the idea behind two stroke dirtbikes is being on the throttle is lubricating the cylinder, off the throttle it’s not

[@lifetextures7106]

@@julianbrelsford The Trabant runs free in the 4th gear instead of engine braking. No need to shift to neutral, only in lower gears.

[@dennisyoung4631]

You might think that there would be a modified oil can connected to the engine crankcase…. Give it a squirt for heavy loads or for descending hills… have a small reservoir to dribble the oil in over a period of thirty seconds or so. Each squirt puts three to ten cc in the reservoir.

[@Kataru.]

Can I just say that it’s amazing you guys pour your hearts into making these hilarious videos EVERY SINGLE DAY? I can’t thank you enough for all the laughs and knowledge I’ve gained from this channel.

[@kurtisriley3019]

100% best educational channel on yt. So much effort put into good explanation and making it fun to learn.

[@lightskinanticsjiggin8129]

They're great !

[@nassermansour5706]

The video‘s a genius

[@gdubya83]

It got more interesting when they added cutting the cheese sound effects

[@jalapenohumpa6599]

Cant stand Jeremiah just want to watch the video not a child

[@jaybockstoce]

If you find a way to spin a turbine (turbo) between the compression cylinder and the last (expansion) cylinder, it might work. You could (in theory) get this thing to make the same power as an old (medium-sized) pushrod V8. If you could maximize the torque potential, I think it would work. In that case, it could potentially work for a utility vehicle.

[@BingTheCheeser]

For anyone interested, the Saab mentioned at the beginning is the Sonett not the Sonic. Neat car.

[@austinrathjen8496]

You forgot the two stroke Detroit diesels. They were in production for awhile until they couldn’t meet emission requirements. There super cool and would make a great episode on their own

[@ellafarm6209]

they definitely need to do one on the old two stroke Detroits

[@jlo13800]

I got a 8v92 silver turbo out back to tinker with.

[@Iamthestig42069]

Coolest sounding diesels period

[@jlo13800]

@@Iamthestig42069 Yes 2 stroke! I have a silver 8v92 out back.

[@brocks692]

Screaming Jimmy's 🤟👌

[@zakaryknight1876]

This might not make for a good automotive engine but with its efficiency it could been good as a fuel powered generator.

[@Creeperboy099]

Maybe a series hybrid application could work? Something like the Regera or Honda’s “E-CVT”? Well, the concept of a two stroke diesel worked pretty well- I don’t know why they couldn’t just apply the same concept to the engine just adding another fuel injection point and replacing the injectors with spark plugs Edit: well Ferrari’s idea was pretty much that second thing I mentioned, specifically referring to the Detroit Diesel (or many larger marine diesels), which had a separate oil system and used a blower for intake pressure as well as had an overhead exhaust valve

[@Creeperboy099]

Wait was this referring to the entry ignition or two stroke?

[@bentboybbz]

nah we would prefer a mustard powered engine

[@yzrippin]

2 stroke more fuel effiecent? Please go back to the workshop and educate yourself.

[@i64fanatic]

good on a lawnmower, emissions are brutal from lawncare equipment.

[@jeremyr7147]

2:45 That's a 4 stoke motorcycle sound clip you played... 🤣

[@cdoublejj]

at around 3:09 you guys used a 4 stroke dirt bike sound clip lol. i bet i'm real fun at parties

[@nigelbassett3791]

This sounds incredibly unreliable. As a rotary owner, having one area of the engine that is way hotter than the rest is a recipe for disaster

[@Megasteel32]

theyll probably put cooling channels around the power piston or something

[@dr.science_0177]

Does the rotary have that kind of problem also?

[@Whiteplane]

If they can cool the exhaust valves on a diesel they can cool the Early Injection area pretty well.

[@centralintelligenceagency9003]

I think that valve going into the bang chamber is going to be its Achilles heel.

[@ulisesavila2879]

@@dr.science_0177 yes, even thou a wankel does 4 stroke steps, due to no having vales it is more like a 2 stroke engine in emissions too

[@jonahfastre]

First piston induces more air into 2nd piston, 4th piston generates a little extra power from the waste exhaust gasses, sounds like a turbo to me, replace piston 1 and 4 with a turbo, oh we made a turbo 2 stroke

[@pyrelogic9876]

Nah, it would be more accurate to compare it to a turbo-compound engine than just a turbo

[@aaronaaronsen3360]

I was thinking about the same thing

[@dantevito1193]

replace piston 2 with a supercharger. this just sounds like another fake engine, super efficient, completely different, and it makes no sense

[@clort123]

I wanna replace the pistons with laser beams and unicorns

[@RookieNoCap]

@@clort123 unicorns are highly sought after on the used market

[@JG54206]

I think it’s worth noting that some MotoGP engineers and riders have said that were the 2 stroke bikes brought back today, with the advances since they were phased out they believe that the 500cc two strokes may be able to make more power than the 1000cc four strokes. Namely things like DI fuel injection, advances in digital engine control, and the continued development of 2 strokes by some motorcycle companies are believed to be able to make a significant difference in the amount of power the engines are able to make. When the regulations first went to the 4 strokes they were much more powerful than the 2 strokes but there have always been some in the industry that attributed that to lack of development being put into the 2 strokes since they were exclusively used in motor sports and power sports. I would sure love to see what a modern day 500cc 2 stroke 4 cylinder MotoGP engine would look like when you let it off the leash.

[@joshuadillman933]

With all the fun and jokes, everything sinks in. You guys have helped me with engine swaps, turbo upgrades, etc... love you guys and thank you. PLEEEEEAAAAASE DO A SAAB 95 AERO episode!!!!!

[@Chris69Hardy]

once again thanks to Donut Media ive learned more than in any classroom. keep up the excellent work guys, Much love from South Africa CPT

[@phammo1]

Jhb here 🙌

[@jordanwilliams4958]

Capetonian here!

[@DonovanBanks]

Sup homies. Out in Durban. It’s poes hot.

[@Chris69Hardy]

@@DonovanBanks Same by us bru, last Saturday was 50 degrees, shits getting crazy out here

[@PippieMomo]

I like how they used the sound of a 4 stroke at 2:47

[@maxmastop1112]

i dont like it at all

[@middlesiderrider]

Same. I wish Donut would get their act together. They often prove they aren't all actually car(or motorcycle) guys, but just actors reading a script. Like when James said the Ferrari F40 had 270hp...I still like them though. Well, most of them...

[@Mike-ie5xu]

That was the least annoying audible thing in the video. They seem to add 7 minutes of 7th-grade "humor" to 5 minutes of content, and that 5 minutes is 70% reliable and accurate.

[@adedhuman9582]

If you have an audience as big as theirs you're no longer gonna want to cater to what are basically 40 year old car snobs. Id say the humor is a good thing since it well, educates and entertains the younger audience at the same time; letting Donut not do that would be gatekeeping

[@hotratz69]

Had me to the end, I loved the concept of the engine as much as your excellent ability to present all of the material , regardless of it's developmental stage.

[@ashlielkerton]

Man I LOVE these engineering videos. They’re so important. Thank you for making them. I love you.

[@whiteking4895]

These guys really are great I can't thank them enough I'm 22 and my dad passed when I was 17....didn't have anyone to learn off of....my pops was an avid mechanic and welder always out and about working if he wasn't with our family....when he passed from lung cancer I didn't know what to do with myself everything I was learning from my dad ended up stopping and yet I had the urge to continue his legacy....donut media has been my "2nd dad" so far and I can't thank them enough

[@aaron6178]

Keep kicking goals young fella. You'll be a dad one day yourself. So you're doing this not just for you, but for your future. Good for you buddy.

[@VFRrider]

My son is now 32. I showed him taught him “man stuff” from an early age. He now out performs me in everything from welding to driving. What I’m trying to say is, I showed him the basics and he went on to improve by practice and research. KZbin played a roll, and STILL does. Hang on in there young man, and rest assured that your dad would be VERY proud. Keep his legacy going, and as the other poster said, you’ll make a great dad yourself one day. Good luck lad. Just remembered a typical example. He was 15 or 16 at the time. We got a puncture on a motorway. I told him to get the wheel nuts ( lug nuts) loose whilst I set up a warning triangle. By the time I got back to the car, it was jacked up and the wheel was almost off . I dragged the spare out of the boot, lined it up, and went to retrieve the triangle when I got back, car was ready to go!!

[@criticalthinkers3787]

Mechanic is a good thing to learn, saves you thousands off dollars a job...

[@Dudesunperfect]

You sound like you have your head screwed on. Good on you mate 👍🏼

[@h00Lia]

💙

[@novemberoscar98]

Being a car guy at heart,but never having had the opportunities growing up to learn about what makes a car do car things, you guys learn me something new everyday. Thanks for that. 👌🏻

[@Bas_Lightyear]

Donut - “Learn yourself something new every day” 👍

[@fridaycaliforniaa236]

If you like deep tech explanations (but easy to understand), may I suggest you two channels : _Driving 4 answers_ and _Engineering Explained_ . Trust me, those two channels are incredibly pleasant to watch 😇

[@widersp13]

I love the content on this video and I remember when you first started I thought you were okay but now you're definitely one of my favorite individuals on this channel and I thank you for the good work the laughs and the knowledge🙏🏾

[@strayboicm6516]

On the topic of how many cylinders it would take to make an equivalent to a regular 4 stroke, I think the most logical solution would be to use the W design like Bugatti uses, since that wouldn’t be too hard to fit in, even if you’ve got a W16 that’s equal to an inline 4, just seems like the most efficient way to fit into a car

[@U.s-epa]

Bro a v4 2t with only 500cc makes more than 200hp. Now imagine a modern v4 with direct injection and ~1500cc.........

[@EddieTheH]

2 smokes need *less* to match 4 smokes. The equivalent of a 4cyl 2l 4 stroke engine would be a 2cyl 1l 2 stroke.

[@tyrecies]

If it turns out to be efficient, it would make for a great hybrid setup. Electric car, but with dedicated onboard generator.

[@PaulIngram487]

Agreed

[@Tuppoo94]

The difficulty may be weight. They said on the video that the engine is pretty heavy, which is fine in a stationary setting like a power plant, but in a vehicle the engine has to move the vehicle and itself. This adds a layer of complexity, because you need a three-way balance between efficiency, power, and weight.

[@metalwolf112002]

I wonder what the chances are of seeing propane powered EVs. Since I work from home due to the vid, my SUV spends most of the time in the garage. Half the time the wife and I take my vehicle it is just to make sure the gas in the tank doesnt go bad. It would be nice if i could just fill the tank with propane once and not have to worry about the fuel going bad because i never drive far enough to use up the battery in my EV.

[@joey7422003]

@@metalwolf112002 You can convert any gasoline car to propane it is about 110 octane but has 20% less energy per gallon than Gasoline.

[@raloed.363]

It also makes it easier to use HHO in the engine

[@kennorcott7074]

You should do more Saab and Saab 2 stroke content. Some of the best sounding 4 bangers ever

[@recitationtohear]

kzbin.info/www/bejne/qqe1g6muoZWIkKc Fax.

[@DanielFrost79]

Sälj Aset Använd Benen = SAAB (A Swedish car Joke) Translation: "Sell the bastard, use your legs" not as fun, but a translation nontheless.

[@Eduardo_Espinoza]

I'm loving the 2 stroke content 👍

[@aspected]

I don't remember any of what I just heard but there's so much fantastic information here presented in a great way. Keep doing these, they're awesome

[@Hexsyn]

This idea blows my mind as much as when I learned about the rotary engine and the Atkinson cycle

[@alexbelmonte4581]

It seems like the concept is “make more use of the fuel we have” instead of “use less fuel”. Which is an interesting take on efficiency. However, it’s hard to imagine how efficient 1-2 cylinders doing the work of 4 actually would be.

[@andrewolson5471]

The added weight, complexity and cost of this engine concept are definitely going to prevent it from ever seeing the light of production. You'd need to basically build a W12 with it to do the same amount of work as a forced induction four cylinder. That doesn't stop it from being an interesting concept, tho.

[@garygrinkevich6971]

It's an "interesting" take alright, it reminds me of how when we started hitting the cap on combustion engine efficiencies, they came up with the 'start stop technology' to kill the engine at idle, and alot of cars these days don't come with spare tires, jacks, or irons, anymore to save on the 60lbs and juice the MPG ratings for a few more digits. Gotta love "creative problem solving" 😏😆

[@draconpost]

@@andrewolson5471 it's actually a nice riddle because one rotation gives power from two cylinders and the other two compress the fuel which reduces the need for a charger and gives more power. In the end it might work like a four stroke with more power gained from compression. So those four cylinders give similar power to a similar sized 4 cylinder four stroke and could have more compression. It's the variety in cylinder size and proper timing that is the problem, it's complicated and needs a lot og unique parts.

[@Lawrence330]

It's "use less fuel for the same work," which is essentially the same thing said another way. Unless, of course, you mean actually reducing consumption by driving less or switching to EVs. But efficiency actually means just what you said, recover more energy from the fuel we are already using. The typical ICE is 25-40% efficient (Priuses, for example, approaching the top of the range). Power plant steam engines might approach 50-60% at best. Theoretical maximums aren't great, and they'd have to improve exponentially faster than in the last 50 years to improve efficiency to match BEVs. There are obvious drawbacks to battery cars, but efficiency isn't one of them.

[@adamnichols476]

@@garygrinkevich6971 Except the start stop is a disaster, and most companies abandoned it for twin turbo engines.

[@JamesSmith-dn8lb]

I always found the deisel 2 stroke opposed piston engine fascinating. It's a shame it never made it to production.

[@fermitupoupon1754]

except for the ones that ended up in trains and boats.

[@dieselgeezer18]

there are opposed piston 2 strokes engines out there. Not in cars though.

[@Thefreakyfreek]

Look up deltic engine I came when I first saw it it just makes so much sense

[@nick4506]

ju86 used them. they were actually pretty common in the 40's but turns out four-stroke diesels are just better for most things.

[@michaelguzzi1]

@@fermitupoupon1754 Aand a few buses and trucks! look up Conmer TS3

[@Mxracer6y]

the irony of using a 4 stroke dirtbike sound when talking about iconic 2 stroke engines

[@JJ_KING246]

hi love your vids just want to say studying engineering is so fun when you said "The one thing about engineer's is they never stop engineering" i was filled with excitement because i love engineering

[@jamesbashaw5831]

2:46 That's a 4 stroke dirt bike sound lol.

[@jamesbashaw5831]

Also, Saab Sonnett, not Sonic.

[@kirtsinghisen8977]

“When most people think of two strokes they think of dirt bikes” -Inserts four stroke sound 😂😂

[@carternevill]

Haha yeah I thought the same thing

[@beanboi7898]

Lmaooo I thought I was the only one that picked that up 😂😂

[@Moustashmol]

that valve between c2 and c4 to me is probably one of the huge issue you didnt highlight, creating a valve that can open an close that quickly enough and at those temp , speeds and pressure

[@carllinden533]

3:18 Y'all really did the Saab Sonett dirty, not you Jeremiah you nailed it.

[@markvicferrer]

The efficiency returns of Mazda's Skyactive X was far less than the tech seemed to imply, but at it's heart, it's still a standard engine. This all new technology seems too complex for it's own good.

[@recyclingbin_]

So my family owned a 2007 Mazda CX7 and it basically had SkyactiveX technology before it was called SkyactiveX. Those models after a while had massive emissions, sludge, and turbo issues because of Mazda's failure to recall known issues with the turbo and engine. $20,000 worth of engine repairs just because Mazda wanted to be cheap with seals and injection valves.

[@EconomyElk]

@@recyclingbin_ eh, more like ford. mazda was still mostly owned by ford back then and their cars were produced in the us using car frames from ford.

[@Nbomber]

@@EconomyElk mazdas of that era had the usual ford rust issues. Those things are complete and total rust buckets

[@Gabiffle]

Hey, I've studied these engines at automotive school, the tech is really more than it seems : Adjustable connecting rod length and microwave "spark" plug Wich allows to compress the fuel more and ignite it entirely at the same time, they get the same efficiency as diesel with those engines, wich was completely unseen before

[@MrHemi4spd]

Its all marketing wank. Put an emblem on the the car that eludes to "blue" "green" or "sky" and its good for the enviroMENTALists.

[@littleshopofelectrons4014]

Some aspects of this engine design remind me of the old triple-expansion steam engine. Three cylinders were used of different sizes to extract more of the thermal energy from the steam before exhausting to the atmosphere.

[@thecloneguyz]

I never understood why it exhausted into the atmosphere when it should go into a condenser and go back into the storage tank

[@BrokenLifeCycle]

@@thecloneguyz Thermal efficiency reasons. Space constraints. Weight constraints. Usually an abundance of water to use during its operation. The times you usually see condensers are when there are either contaminants in the water that shouldn't be released into the environment or turbine, or there's a scarcity of water. Nuclear reactors that directly boil water (in contrast to indirect cycles that send it to an isolated loop) will definitely want a closed cycle loop because that steam is now mildly radioactive. A closed cycle loop in general would mean outside contaminants are less likely to be introduced to the sensitive turbines compared to if fed from an unfiltered source like a river. Some steam trains have been fit with condensers simply because there was a scarcity of water in the area they operated. But in general, condensers are a source of inefficiency. Heat engine efficiency is a direct relation to the temperature difference between the hot reservoir and cold reservoir of the system. Condensers introduce a restriction to the rate waste heat can be rejected from the working medium and into the surrounding air. If the working medium cannot be cooled back down to ambient temperatures, you've effectively raised the temperature of the cold reservoir and reduced efficiency.

[@TheLtVoss]

@@BrokenLifeCycle I would add that I read samething about train condensers where used during Wars so that the trains had to stop less /stay moving or to reduce the visibility a bit even saw a picture off a steam Lokomotive with 2 condenser wagons behind the Tender

[@TheDutchGuy110]

The steam is condensated into water to be boiled to steam again to repeat the cycle Also it's about pressure not heat that's why you have a high, intermediate and low pressure cylinder in a triple expansion engine

[@shaider1982]

Drachinifiel had a good video on steam engines for warships

[@PullStartStables]

You really know your stuff, that’s easy to see! I like the humor, along with the info!

[@comptegoogle511]

An electric supercharger with a three-stage compound compressor can easily bring the compression ratio at 12/1. Then the intake air would be very hot so a lot of this heat could be lost in a liquid intercooler. then it could go into a Detroit two-stroke with a TDI system working at 20/1 to 40/1 compression ratio inducing a very efficient burn of the diesel. The hot gas release could be used to spin a multi-stage exaust turbo to recharge the battery of the car and the supercharger. So it would be an hybrid between a turbo-prop for the compact high HP, a Detroit desiel for the low RPM tork and an electric car to store and release the juice at will. To increase the efficiency even further, the intercooler could be cooled with ammonia, and the evaporated gas coming out of the intercooler could be used to spin another turbine attached to the exhaust turbine shaft (like a steam turbine) to recuperate even more energy and cool down even more the intake air.

[@acey_570]

my favorite thing about jer-bear is he goes from dropping some serious knowledge, showing just how educated he is, to doing a weird voice and saying or doing something absurd. you are hilarious. never change

This engine actually makes me think of a triple expansion steam engine based on its rudimentary design :D

[@scottthewaterwarrior]

I had the same thought, compound locomotives, I forgot they made a few with three sets of pistons.

[@curtchase3730]

I hope you enjoyed your 10 minutes of heat with that power station! I know, just a demo. My jaw hit the floor when you mentioned the Saab "free wheel" system! I been there, done that. Had a 1968 96 sedan, not the Sonnet, w/the 3 cylinder 2 stroke and a few w/the V-4 4 strokers, all w/free wheel. Loved them. The 2 stroke did blow up at only 65,000 miles! Used needle bearings! The Sonnet "may" have had a 2 stroke model, but most were the English Ford V-4's. Oh ya, that funky entry ign engine kinda reminds me of a triple expansion steam engine, like the Titanic had.

[@jonahcollyer8165]

You guys really are the best content creators on KZbin 👍🏻👍🏻 love every video!!

[@max-zl1vm]

He’s much more cool calm and confident than his first videos. Props to the rest of the group for helping to build him up.

[@Swangbang]

You deserve a real comment for this observation not just a bot

[@blacktc250]

Loving the fact that when he shows the two stroke dirt bike it makes a four stroke sound

[@fennex7575]

that killed me

[@aidenearley2377]

I'm just glad we got to listen to Jeri's amazing pronunciation of oil again.

[@kennetharmas1842]

Sending love to Jeremiah keep your head up brother. They're going to figure out all the strokes for all the folks.

[@chieftron]

@3:20 It wasn't the Saab Sonic, it is the Sonett, that specific one is the Sonett 2. The Saab Sonett 1 was a super sport prototype that looks amazing even to this day.

[@RantDuJour]

🇸🇪

[@MrTheheds]

Well said and you spelled it correctly too.

[@Bas_Lightyear]

Ohhhhhhh I thought it was the Maverick Saabre that had the 2 stroke, he’s a good bloke, smoke don’t choke engine 🤔

[@SemtexWarrior]

Went to comment this but i see i don't have to. However i can add some more info, the name Sonett comes from the swedish phrase "så nätt" meaning to be light and/or nimble. It's kind of a hard word to translate but that is the most fitting translation i can think of.

[@horndogjr]

Nerd...good info though

[@Benquay12]

Seeing these videos makes me laugh even more thinking of Jerry’s first few videos. That’s on character development💪🏼✅

[@hyundaitib2]

Thank you for going to school and sharing your knowledge 🙏 so appreciated

[@sethanderson9931]

You should do more two strokes video’s!

[@xoh-kp6kr]

There's one from a few months ago

[@spikes_johnson]

If they keep talking about 2 stroke engines like this, I wouldn't be surprised if they tried to do a motorcycle engine swap on a car

[@Benquay12]

2 stroke in the D-list Jetta?👀

[@spikes_johnson]

@@Benquay12 Lol it couldn't hurt it any more than it is

[@kevobrando95lx44]

@diana p y'all are walking burnt toast

[@gabrielv.4358]

Brazil did that. In a Fiat Uno. HA!

[@spikes_johnson]

@@gabrielv.4358 Seems like an appropriate car to use. Nice and small

[@josephestrera419]

I like the humor dude it all adds to the great topic of the video

[@tankeater]

2:48 You used the sound of a 4 stroke Dirt Bike... That's depressing and also lack of attention to detail. 2 stroke bikes sound absolutely STUPENDOUS, and you got it qeong

[@JJs_playground]

That comment about Blockbuster able to buy Netflix for $50million, was Savage and so very true. But in way, glad that blockbuster didn't buy Netflix, it probably wouldn't be as good.

[@ellafarm6209]

You guys need to do a dedicated video on the two-stroke Detroit Diesels that were made from 1940 to 1995 and were put in literally anything from generators, trucks, heavy equipment, tractors, and even boats. The sound these engines make is legendary and practically helped to built America in the mid to late 1900s

[@onecanadianchip]

Tanks and armoured vehicles aswell such as the M4A2 had twin 6-71s known as the GM 6046

[@Sniperboy5551]

As a huge fan of Food Network when I was a kid, I really appreciate the Emril reference 😂 It makes me feel like I’m not too old

[@bonovoxel7527]

"Will 2strokes engines save us from EVs?" *John Connor tryin to escape the Terminator on his dirt bike. YES!

[@jakevella3904]

Jeremiah seems so natural in front of the camera and he makes these videos just as entertaining as James did

[@Tommy-ye5vf]

thats the cocaine

[@iMaruchaaan]

This dude is th funniest guy on this show hands down

[@johndymond6588]

Never heard of this design. Really interesting idea. The balance issue could be alleviated perhaps if you built the engine in a circular design; but that would likely be bulky, difficult to assemble, and nearly impossible to do maintenance on. Great vid!

[@barnettzack]

My Subaru converted it’s self into a two stroke

[@andrewolson5471]

That sounds like a bug rather than a feature.

[@Tyguyborgerding]

Speaking of new engine tech, you guys need to check into the Astron aerospace omega 1 engine. Really cool and really simple!

[@Nightingale1887]

Would be interesting to do a special about the six stroke engine or the Hüttlin kugelmotor (bullet engine) these are very interesting designs. And they actually exist instead of only in concept stage.

[@strongishpath1556]

Yo that intro AD had me lmao at the end. “Cause not everyone lives in Southern California” I live in Vermont. The hottest and coldest place on earth

[@DennonOosterman]

Hey now, 2 stroke technology has come arguably almost as far as 4 stroke technology. The new 850 Etec by Skidoo is an absolute monster of an engine with some incredible technology. 1. Direct injected - just as efficient and clean burning as a 4 stroke. As far as I know, ETEC engines are the only DI two strokes in the world. 2. Electronic *everything* from timing to fuel to oiling etc. 3. Electronically controlled exhaust "valves" (change the port size / shape based on RPM to maximize low end torque and top end power). 4. Want to go backwards? No transmission needed. The engine literally changes timing on the fly and *starts running backwards at the crank*. 5. It's a pump gas, consumer friendly engine that puts out ~170hp from 0.85L of displacement, naturally aspirated. ONE HUNDRED AND SEVENTY HRSPRS! From 51 cubic inches!

[@gypsymike2355]

Most drivers can’t figure out how to use their indicator lights … and you expect them to do the math on 50:1 per litre or gallon

[@asas-mb4wj]

They make things that automatically add the oil. Been around a while

[@ohioplayer-bl9em]

@@asas-mb4wj the driver would complain that the vehicle was burning to much oil..

[@noname-wo9yy]

@@ohioplayer-bl9em Mazda Rx 8 burned oil

[@bryce8248]

Jeremiah is one of the best additions to the cast. It's natural to him.

[@Monty16v]

Cringey guy

[@fololoco6420]

No he aint

[@bryce8248]

@@fololoco6420 cool, your opinion and you’re welcome to it.

[@fridaycaliforniaa236]

And Zach is also really good at this. His videos about the Miata are some of my favorite on YT =)

[@aaron6178]

This was sick. You're a great educator man hhaha. For real.

[@Box_Of_Ducks]

Don't forget one of the most produced diesels for decades after WW2 was the Detroit 2-stroke line, making engines on mass from small 4-53s all the way to 8v92s in standard applications

[@gabrielv.4358]

Yes. Detroit two strokes are amazing at making sound

[@substandardabuse6028]

Detroits are boss

[@randomtuner8786]

3:20 *Saab Sonett As a swede I am greatly offended

[@ka24det]

Thanks for that.

[@kennorcott7074]

As a Saab enthusiast I agree. Sad

[@reynardkitsune1]

A lot of (European) car manufacturers used the two-stroke, though most of them went either defunct or switched to the 4-stroke after WWII. One of them was Aero, a Czechoslovak company who had built the largest two-stroke in serial production (Type 50, 1997 cc 4-cylinder, 51 hp). Apart from emissions, another major problem of the two-stroke is that the piston displacement can't be chosen as freely as in 4-strokes. As a general rule, the maximum displacement should not exceed 350cc per cylinder for the optimal power to weight ratio. Two strokes do achieve a good power output by revving high, but the disadvantage is the limited torque which is only available in a narrow band. This disadvantage could be at least reduced with automatic multigeared transmissions but not completely eliminated. Direct injection was mainly used for small engines. While the emissions from the mixture could be vastly reduced and catalytic converters were easier to adapt, these engines were far more expensive in production and had some issues with the reliability.

[@austang8556]

Thanks for sharing!

[@LemonMontage420]

Hey Jear Bear, could you do an episode on how the liquid piston X engine works?

[@kyleyates8172]

Based on the fact that it's still making power even during the exhaust stroke would mean a more even power curve, so while it might not make sense for cars, it would make generators a lot better by having a more constant torque curve and smoother input to drive the electrical components, making them less prone to frequency changes and power loss under load unless I'm missing something, and anything to make a more effective generator has a market available

[@F14thunderhawk]

yes, youre missing that this system is superior when handled by a turboshaft engine, not a piston engine. The best possible engine for a car would be an opposed piston engine, which while they are extremely delicate due to implicitly requiring a Roots or screw supercharger to function properly, and theyre extremely expensive due to requiring male and female piston heads and 2 machined engineblocks, combine all the advantages of the Otto and Clerk Cycles with a minor increase in friction and weight.

[@T..C..M]

Rob Dyrdek & Daniel Tosh had a son and he’s in this video.

[@Dud3itsj3ff]

That cheese man but at the end was cracking me up fr 😂

[@Billboi805]

I’m not an engineer, but I feel like this is a cool theory but I think it would be absolutely ridiculous in practice.. I really want to know what it would sound like though

[@alexandersteele4212]

Jeremiah is awesome and hes easy to listen to cus he teaches us so much he deserves to be on donut just like everyone else

[@alexandersteele4212]

@diana p quit that shit please

[@kilroywashere9678]

It’s crazy, when Jeremiah first started hosting B2B I couldn’t stand him, now he’s one of my favorites.

[@alexandersteele4212]

@@kilroywashere9678 yeah he really improved alot

[@TheKnarlyKarly]

Wow. Great explanation of an incredibly complex design. I hope they at least get a prototype built and running, just to prove it works, whether it ends up being feasible and practical or not.

[@ramcharger9146]

I have a two-stroke dump truck from the 40s running great

[@derekrebel3384]

Been loving the 2 stroke content. Their relative simplicity in motorcycle applications has really helped helped me begin to understand engines. Doing my first top end rebuild soon and I’m excited to do it!

[@Usiris23]

Love the pug profile pic

[@hayden6119]

Mixin gas and slappin ass 💨

[@Toxic2T]

@@hayden6119 You said it, brother!

[@justsilent8955]

Could be an interesting option for generators in back up power grids gets rid if the varying engine load

[@SirDrakeNewcanon]

I had a Wartburg 353S, it was a lovely car! I once blowed up the engine! With a new engine, I used it for years!

[@MrShwaggins]

Lube fixed my 2 stroke problem. I'm a man with limited time and it made it a one stroke job!

[@karmA2q]

Watching Jer getting hyped about engineering is a great way to wash the sour taste of Monday out of my mouth. Keep up the amazing content!

[@bentboybbz]

Are you sure thats monday and not leftover from saturday?? lol sorry i had to

[@shifty1927]

I have a 670ho rotax 2 stroke from skidoo in my 85 honda odyssey. Super easy swap thanks to CVT. 130HP in a little over half a liter.

[@aaronaaronsen3360]

The same power as the 1125cc Rotax from my Buell. Impressive

[@bentboybbz]

but no emissions regulations and would probably not do well at all in anything but a snow brapper

[@shifty1927]

@@bentboybbz those engines do amazing in my mini buggies. Also great for airplanes (one of the most popular rotax engines the 582 is for flight) and apparently great for scat hovercraft also lol cause the guy that built cleetus McFarlands hit me up for a 670. They're great in anything you keep the rpms up. Hence 2 stroke power band

[@shifty1927]

@@aaronaaronsen3360 yea its wild the hp you can get from an engine the size of a shoebox. its a fuel monster though. I have a ported high compression one that should be making at least 140. Neither has the drivability that your buell probably has lol

[@bentboybbz]

@@shifty1927 I should have been more specific. I meant in a road going vehicle. You are right for sure. I've seen some pretty awesome builds. I e never had the chance to really play with anything rotax. Hope you are having a Great Day sir!

[@maximilianlode2859]

2 stroke dirtbike driving trough backround with 4 stroke sound xD

[@leighp03]

jeremiah Cheeseman, has a great ring to it hahahaha Love the content Donut crew

[@aaronjones9196]

Coming from a recent mechanical engineering grad and a car enthusiast, THESE VIDEOS ARE GOLD.

[@vorpalblades]

These guys are clowns.

[@aaronjones9196]

@@vorpalblades how so?

[@vorpalblades]

@@aaronjones9196 this video is a perfect example. 18 minutes spent on something that doesn't even have a operational prototype. Or is even feasible at this point. Engineering Explained and Driving4Answers are channels with actual engineers explaining valid concepts. These dudes spend too much time shouting stupid shit.

[@Donut]

🤡

[@aaronjones9196]

@@vorpalblades the title literally says “Why There Aren’t More 2-stoke Cars”. Wtf did you expect this video to be about 😂

[@josephshaffer4491]

If they used larger intake cylinders to feed multiple power cylinders at one time, it could in turn lower the weight and make it easier to balance, may even be more efficient.

[@blue.dt2000]

So basically a supercharger but without the belt driven part

[@davidmilligan4751]

would it not be easier to just replace the extra cylinder for intake with a turbocharger hell you can even remove the 4th cylinder to provide extra flow for larger turbos this would both simplify the design and bring us back to the 1960s turbo charged 2 stroke engines used in motorcycles of that era the only difference being that instead of using a spark plug to ignite the fuel air mixture you now have some fancy valve instead?

[@ayoutubechannel921]

Or they could just use a supercharger that does the same thing, would save tons of weight too

[@nuclearpowerphysics5409]

7:00 "massive and efficient, stop it 🥵" 💀💀💀💀

[@troydorr4867]

Very cool! You guys are awesome!

[@DawsonTyson]

This is probably a good idea for a generator. Set engine speed with a designed max load and increased efficiency, but otherwise most likely 🗑

[@purwantiallan5089]

Yes.

[@anomilumiimulimona2924]

Thats what i thought, exept id ditch the precompression cylinder and add a turbo.

[@DawsonTyson]

@@anomilumiimulimona2924 a root may work better no way to know without a couple of prototypes.

[@travisuysaloglu9695]

@@DawsonTyson turbos are better for gens because they're more efficient.

[@anomilumiimulimona2924]

@@travisuysaloglu9695 yea, low parasitic loss, couple that with the constant target rpm of generators, and a proper boost map out for the turbo.

[@Bdub1952]

The complexity of this arrangement only makes the simplicity of electric motors that more compelling.