Learn more about HORSE:
https://www.horse.cars/
https://www.linkedin.com/company/horsepowertrain/

In this video I do something that I have never done before and that is to go inside an actual engine factory. And this is not just any engine factory, it's a super modern engine factory that manufactures 1 million engines per year, or 1 engine every 11 seconds.

The factory belongs to HORSE. Who is Horse? Well, they stated off as a sub-division of the French car giant Renault, but currently they're a joint venture between Renault and Geely from China. Renault and Geely each own 45% of the company while Aramco from Saudi Arabia owns the remaining 10%.

The video covers the entire process of an engine taking birth, from the very raw materials right down to a completely finished, dyno tested engine ready to be installed in a car. This is possible because HORSE's Valladolid factory is essentially an engine manufacturing one-stop shop. It's more like a small city but you get the point. The process starts at the foundry where they do pressure casting and pre-machining of the engine blocks. Here we will see how HORSE reduces their costs by 3D printing replacement parts for their manufacturing machines and we will see engine block pressure casting as well as die maintenance using 3D scanning.

After that we go into the machining section of the factory. Here we will have the opportunity to see the revolutionary bore spray coating process. This a process where melted steel is sprayed right onto an aluminum engine block which is then later machined and fine honed. The result is that we create micro-pores in the cylinder where the oil can stick and allow lubrication together with reduced friction leading to improved economy and emissions as well as a reduced engine block weight. This is pretty amazing because the cross-hatching of the cylinders most of us are familiar with is no longer present nor necessary inside the engine. In the machining plant we will also see the honing process as well as numerous machines in charge of control and cleanliness. What's especially impressive for me is a 500 bar water jet machine that can remove bore spray coating steel residue without harming the aluminum engine block itself. What's also really fun to see is that each engine is tracked with an RFID tag that contains the data matrix of every engine which is also uploaded into a cloud to allow a big data analysis and monitoring of the entire manufacturing process.

After the machining process is completed we proceed into the last phase which is the assembly process. The assembly plant is a miracle of modern planning and logistics. Here we will see AGVs or automated ground vehicles ensuring timely distribution of engine parts. We will also see how the engines are tested again and again for leaks in the high pressure oil, low pressure oil and water systems. The final leak test involves helium being injected into the engines and then a specialized sniffer robot checks the presence of helium molecules around the engines to detect any leakage. We get to see an axial play check, gasket material application, main bearing plate cross-bolting sequence, rod bearing installation, piston and rod assembly installation as well as optical checking of the piston and rod assembly. One of my favorite parts was a robot hand that holds a tissue and wipes the timing chain cover mating surface. It then throws the tissue into the garbage can.

The assembly process is finished off with both a cold-dyno and a traditional dyno where the engine gets started and verified for the first time to see if it's running right. On the cold dyno the engine has fluids but it doesn't get fuel and it's spun by an electric motor to reach target rpm where outputs from various engine sensors are checked. On the hot dyno the engine is connected to a system of fluid and fuel supply along with all the sensors and is ran at 500 rpm increments up to 3500 rpm.

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#d4a #enginefactory #horsepower

00:00 Entry prep
02:48 Casting
07:03 Bore Spray Coating
11:37 Cleaning and Machining
14:24 Assembly
21:36 Engine Start and Testing

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What is the best engine configuration?
My default answer is that there is no such thing. Different configurations excel at different things so the answer depends on your goals, needs, application, budget, space and various other factors. In other words, there is no best engine configuration in the absolute sense. But if I was forced to choose a configuration that is the best, the most representative configuration of reciprocating piston greatness, an ambassador of internal combustion glory then it would HAVE to be the V12 because there is no other engine configuration that has a comparable blend of power, balance, smoothness, sound and history as the V12.

The first V12 engine was built in 1904. 120 years ago, by Putney Motor Works in London for use in racing boats. It was called the "Craig-Dörwald" engine. The first famous V12 powered car was called “Toodles V”, it was the brainchild of Louis Cotaalen, the chief engineer of the Sunbeam Motor Company. It was a 9 liter 60 degree v 12 that was rated at 200 horsepower ar 2400 rpm and weighed 340kg. Toodles V broke multiple speed records in 1913 and 1914.

From the world of racing and one-off custom builds the V12 proceeded into the world of luxury. Some of the first production cars to have a V12 came from the United States, a country that is most certainly not associated with V12s today. But back in 1915 US-made cars like the Packard Twin Six, The National and the Weidely were pioneering a new era for high-end cars.

The power and smoothness of the V12 proved to be contagious and the configuration spread like wildfire. Throughout the roaring 20s and even the 1930s the V12 became the engine of choice for the flagship models of pretty much all the relevant manufacturers of the day. Fiat, Daimler, Maybach Horch, Hispano-Suiza, Tatra, Rolls-Royce, Cadillac and Lincoln to name but a few. In an age before insulating engine mounts and modern performance dynamics, the V12 ensured silky-smoothness and increased power with an increased number of cylinders.

The 1930 soon spiraled into a crisis which culminated in the 2nd world war. This time of immense destruction and tragedy for humanity was also a time of massively accelerated evolution of engineering and technology. This age gave us some of the most iconic piston engines in history. Rolls Royce Merlin, Mikulin AM-38, Daimler-Benz DB-600, Allison V-1710 and Junkers Jumos were among the most iconic ones. They powered unforgettable fighter aircraft such as the Spitfire, the P-51 Mustang or the Messershcmidt BF 109.

After the war the car industry started recovering. And a man named Enzo Ferrari remembered the smoothness and power of pre-war V12 engines. So in 1947 him and Gioacchino Colombo made the Ferrari Colombo V12 engine. The engine that would put Ferrari on the map and build the foundations for everything that was to come. The Colombo powered many iconic Ferraris well into the 80s.

But a man named Lamborghini thought that Ferrari V12 engines sucked so he commissioned a Ferrari engineer, Giotto Bizarrini, to make him a new V12 for his newly established racing car brand….a bit of a weird logic, but it lead to incredible results. Introduced in 1963 the Bizarrini V12 would power flagship Lamborghinis like the Countach, Diablo and Murcielago for half a century.

V12 didn’t just power expensive flagship supercars. They were also present at the heart of the world’s highest class of racing, Formula 1. Legendary V12 engines built by Honda, Ferrari, Maserati, BRM and Matra powered several iconic Formula One race cars throughout the 60s and the 70s. Honda’s V12 was the last V12 to win at Formula 1 in 1991 with The Mclaren MP4. 3.5 liters, 60 degrees V12, 14.000 RPM, Six Speed Manual. Ayrton Senna behind the wheel.

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#d4a #v12

00:00 History
10:51 Anatomy
14:58 Sound

No description provided.

Here's a look at the one-way bearing I feel didn't elaborate enough in the main video.

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In today’s video, we’re taking a deep dive into Honda’s newly announced V3 engine with an electrical compressor that according to Honda will become a production engine in the near future.

In this video we will cover:
1. The anatomy and benefits of a V3 engine layout
2. The benefits and consequences of an electrical compressor
3. The engine balance of a V3

Overall I think this is a very interesting engine and approach to powering a motorcycle with many interesting benefits and challenges, so let’s dive right into it.

A v3 engine is in theory great because it has the width of a two-cylinder and the power potential of a three-cylinder. The layout is two cylinders in the front and one cylinder in the back. This allows us to have a very narrow motorcycle which reduces aerodynamic drag and can also improve comfort and maneuverability.

On the other hand, a V engine compared to an inline engine does force a somewhat increased wheelbase but in this particular case, Honda’s V3 is a 75-degree V so it’s not quite as a wide as a typical 90 degree V engine which means that it’s trying to strike a compromise by reducing the engine size a bit while at the same time leaving enough room for a performance-oriented intake system. There is no official info on engine size yet, but most reports suggest that the engine will be between 750 and 800cc of displacement.

From what we can see in the pictures and in the press release this is obviously a water-cooled engine as there are no cooling fins of any kind present and we can clearly see a water pump present. We also have a centrally located spark plug…and twin camshaft seals which tells us this is a double overhead cam engine with four valves per cylinder. So, it's pretty much a typical modern concept promising good performance. The engine is also obviously not some sort of one-off machined from billet thing, but it seems to be made up of production castings which suggests that this is engine is likely in the last stages of development and may be very close to production.


Of course one of the more interesting features is the electrical compressor. Now, some journalists have been calling this an e-turbo or an electric turbocharger which is incorrect. It’s incorrect because for something to be called a turbo it must have a turbine and a turbine is is a rotary mechanical device that extracts energy from a fluid flow and converts it into useful work. That fluid can be wind, it can be water, it can be exhaust gas.

But in this case, there is no turbine, instead,d we have an electrical motor doing the job of a turbine. The electrical motor does not extract any energy from any fluid but is instead of course powered by electrical energy and herein lies the beauty of this device.

If we’re using an electromotor to spin up the compressor wheel it means that we are completely independent of the exhaust gas flow which has many important benefits.

We can spin up the compressor to full speed and create maximum boost whenever we want. Instead of waiting for the engine to reach a certain rpm where it builds enough exhaust gas for the turbo to create a certain boost we can spool up the compressor to the desired speed even at extremely low rpm. In other words we can transform our torque curve from something like this……..to something like this. We can create an extremely flat torque curve that remains flat for most of the rpm range. Effectively we have zero boost lag and near-idle boost threshold which results in exhilarating performance and maximized engine responsiveness
Because we are independent from the exhaust gas we do not need to create complicated exhaust manifolds that all feed into the turbocharger which means reduced weight and bulk and cost. Because we don’t need complicated exhaust manifolds we can place our electrical compressor anywhere and as you can see Honda has of course placed it extremely close to the intake manifold for maximized responsiveness
We can potentially make more power with an e-compressor than a traditional turbocharger and that’s because contrary to popular belief a turbocharger IS NOT free energy. Yes it extracts energy from what is essentially engine waste BUT it still presents a bottleneck in the exhaust. If you look down the turbine inlet of a turbo you will see just how small the space is into which exhaust gas needs to be pushed. This creates significant backpressure that the engine must overcome and that consumes energy.

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#d4a #honda #v3

00:00 V3 Anatomy
02:17 Electrical Compressor
08:08 Engine Balance

https://www.ratiozero.com/
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Today I have the privilege to hold in my hands something special. It is called Ratio Zero and it is the worlds first operational gear based cvt But before I explain how this piece of mechanical poetry actually works allow me to first explain why a gear based CVT is a big deal.

As you probably know CVT stands for continuously variable transmission and from the perspective of fuel efficiency, smoothness and ease of use they are the ultimate transmission. And while I would not choose a CVT transmission for a vehicle that I want to take to a twisty mountain road or to the track where I want to enjoy revving the engine out through the gears, I would gladly choose a CVT for a vehicle that I drive everyday on the highway or in boring stop-and go commuter traffic.

A traditional manual or automatic transmission has a set number of gear ratios or speeds

For example, a gear ratio of 3.6:1 tells us that for every 3.6 revolution of the engine, the wheels only make one revolution while the torque at the wheels is increased 3.6 times. So the frist gear reduces vehicle but increases torque, this is why it’s used for getting the vehicle moving from a standstill and top climb steep hills.

A manual or automatic transmission will usually have anywhere between 4 to 8 such gear ratios which we call speeds. Compared to this a CVT will only have two “gear ratios” or speeds. This is because a cvt does not have gears Instead we have two conical pulleys and a belt or chain running around them. We slide the belt along these pulleys and the different sizes of the pulleys at different parts of the cone simulate an endless number of different gear sizes which means that a CVT has an endless number of ratios in this range between its lowest and highest ratio. So if an automatic or manual is a 6 speed or 7 speed or whatever than a CVT is a million speed transmission or an infinite number of speeds transmission.

Ok, if CVTs are so great why aren’t they more popular? Why aren’t they on every car, truck, motorcycle, bicycle?

Well, that’s because traditional CVTs, they kinda suck.

Their first problem is that although they help the engine be more efficient, they themselves are not very efficient at all and that’s because friction is at the very core of the design of a CVT. If you observe the inner workings you will see that torque is transferred between the pulleys by a belt or a chain. The belt or chain has nothing to grip onto, there are no gear teeth, no notches, no grabbing points, which means that the belt tension or the friction between the belt itself and the smooth surface of the pulley cone are the only thing transferring the torque. Which means that to transfer substantial amounts of torque we need substantial friction and as we know friction leads to efficiency losses, heat and wear. This is why a typical belt or chain CVT in a car is around 80-88% efficient, a more simple scooter CVT is around 70-75% efficient whereas a geared manual transmission is 95-97% efficient in almost all applications.

This is why researchers, inventors and many others have been trying to create a transmission that combines the smoothness, ease of use, fuel efficiency and continually variable gear ratios of the CVT with the torque capacity and low friction of a geared transmission.

Despite repeated efforts there has been little success, until in 2016 a man named Edyson Pavlicu had a breakthrough idea - to split the rotation and create the world's first geared CVT transmission - Ratio Zero.

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00:00 The Problem with Manuals and Automatics
04:24 The Problem with Traditional CVTs
08:03 Splitting The Rotation
15:12 A Better Prototype

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The amazing thing about valveless pulsejet engines is that they are the simplest known engines and that’s because they have zero moving parts, essentially they are just a hollow pipe of varying shape and diameter. That’s it. Just like our glass jar.

Despite their extremely simple anatomy their working principle is in fact pretty complex and can be difficult to explain and understand and that’s because inside a pulsejet we have three distinct processes that occur simultaneously to ensure their continued operation.

The first process involves the fluid dynamics caused by the combustion of the air and fuel inside the combustion chamber of the engine
The second process is acoustic and involves the sound waves created by the combustion
The third process is thermodynamic and involves the rapidly changing temperatures of the gasses inside the engine

So as you can see a lot of stuff is going on making things kinda complicated, but if you do manage to properly understand a pulse jet I promise that you will gain a new multi-disciplinary appreciation and understanding of the amazing things that physics can do, even with zero moving parts.

The pulsejet shape we will be using for our explanation is the Lockwood - Hiller which comes from the early 60s is sort of a culmination of a hundred years of trial and error and is probably the most popular design by far today and that’s because it offers a really nice balance of ease of starting, thrust, efficiency, and reliability.

The main parts of any pulsejet engine are the intake, the exhaust and the combustion chamber.

To start the engine we will inject fuel, in most cases this will be propane from a tank that will be injected either directly into the combustion chamber or in front of the engine at the intake. We will also install a spark plug inside the combustion chamber. The spark plug is needed only during the starting phase and is not used later.

So let’s imagine we have opened our propane valve and allowed fuel into the chamber. Because the engine is a hollow tube we already have air inside it which means that now we have an air-fuel mixture in the chamber. We ignite that air-fuel mixture which causes it to combust. As the combustion flame front expands it increases the pressure and temperature dramatically. This expansion of the combustion forces and accelerates the masses of air in the intake and the exhaust out of the engine. Now a jet engine is a reaction engine. As you know for every action there is an equal and opposite reaction. So by accelerating the air mass in one direction the reactionary force moves the engine in the other direction and if we attach that engine onto something that something will move together with the engine. So what we have inside a pulsejet is something that was called thermal breathing by Francois H. Reynst, who is considered one of the most important pioneers of modern pulsed combustion. So if pulsejets are so simple and they can produce thrust why aren’t they more widespread?

Well, first of all, they have poor fuel efficiency. One of the reasons behind that is that we are igniting the air fuel mix with the heat of the exhaust gas. That means that we always have a mix of exhaust gas air and fuel upon ignition which is less then ideal leading to an incomplete burn of the fuel which then gets spit out the intake and exhaust. The other reason we have poor efficiency is that there is no active compression. A turbojet or a turbofan have a compressor section consisting of several stators and rotors which easily increase the pressure of the air five times over or even more. A pulsejet only has atmospheric pressure at it’s disposal. When we ignite compressed air and fuel we achieve a much higher combustion temperature which not only helps to burn the fuel more completely but it also achieves much higher combustion pressure leading to higher thrust. Another reason why pulsejets produce less thrust is the intermittent nature of the combustion which is simply less capable of producing high thrust compared to the constant combustion inside a turbojet or a turbofan.

The final drawback is the noise. Pulsejets are incredibly loud compared to most other engines. Despite their drawbacks, pulsejets are by far the simplest and cost effective way of achieving powered propulsion or flight making them an ideal candidate for RC planes and other unmanned aircraft.


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00:00 Glass Jar Jet Engine
03:46 Operating Principle and Fluid Dynamics
12:16 Acoustics
17:28 Thermodynamics
18:55 Drawbacks and Benefits

#d4a #pulsejet

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Question 1. How come the vanes don’t scrape against the ports.

This was a very common question and honestly, I’m surprised that it was so common.

The little 3d model in the previous video is obviously a cross-section of the engine. While it may seem like the vanes might catch onto the port in the fully frontal cross-sectioned display of the model it is also very easy to imagine how the vanes do not catch onto the ports because the vanes are larger than the ports, this is the intake port of our little prototype and this is the exhaust port. As you can see the vane does not fit inside any of the ports as it passes by so obviously if it doesn’t fit inside it can’t catch onto it. The difference in port size vs vane size is also shown in the previous video but seeing that requires watching the video before commenting which of course is asking too much.

Ok, Question 2. In the previous video I have said how the rotary vane engine is a vibration-free engine. Many people commented how I was wrong because the vanes move up and down and this creates vibration.

I’d like to draw your attention to the fact that each vane is opposed by another vane. When one when is extending so it is the opposing vane. When one when is retracting so to is the opposing vane. The same thing happens in our prototype. The vanes are of equal mass, they are perfectly opposed and they create forces of equal magnitude and opposite directions which means that the forces creates by the vanes cancel each other out. It doesn’t matter how many vanes we have, four like in the animation or 6 like in our prototype. As long as the number of vanes is even we will have an engine with zero vibrations.

Question 3. The springs will fail.

I honestly have no idea idea why this comment was so common? We have valve springs in piston engine right? Are they a frequent point of failure? No. They aren’t even a service item. They last the life of the engine. There is no reason why the springs in a vane engine would be an issue as nowadays we can manufacture extremely durable springs at affordable prices. I really have nothing special to add here.

Question 4. Clearance between housing and vane tips

In the last video I have also mentioned how centrifugal force drives the springs into the housing which increases wear and have suggested piezoelectric actuation as a form to prevent the vant tip from contacting the housing. There have been several comments that responded to this by saying how it’s impossible for piezoelectric actuation to manage the large movement of the vane since piezoelectric actuation can usually only handle ranges of a few micrometers.

And yes, this is correct. But I never said that piezoelectric actuation would handle the entire movement range, because 1. It can’t and 2 it doesn’t need to. If you observe our model in slow motion you can see that as soon as we initiate rotation of the engine, centrifugal force flings the blade outwards. There is no need to control their entire range at all. Piezoelectric actuation would only handle the last few fractions of a milimeter in order to maintain a no-contact gas seal. Such piezoelectric actuators could either be embedded in the housing or in the blades themselves.

Alternatively piezoelectric actuation can be used together with mechanical blade control systems to ensure a no contact gas seal because there are realistically numerous mechanical ways to control the blade movement. For example in 1967 Popular Mechanics published an article about a 400 horsepower vane engine that used a cam in the center of the engine to control blade movement. Another example is this system conceived by an inventor from Poland, which incorporates a predetermined track through which vanes and vane guides roll during engine operation. This is a simple system that leads to reduced friction and wear. One of my subscribers sent me this email after I published the last video where he suggests incorporating gears to control vane movement which is another viable solution which was in fact already patented in the past. So as you can see there many different ways to control blade movement, of course which one of these ways is best suited for what kind of application and budget must be discovered through methodical research and development efforts.

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#d4a #rotary #rotaryvane

00:00 How it's made
04:53 Q1: Vanes catching on ports
06:05 Q2: Engine balance
07:24 Q3: Springs
08:45 Q4 Piezoelectric actuation
11:42 Q5 Vanes will fail
14:05 Q6 Uneven heating
16:40 Start attempt

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If you have ever observed dirt bikes you have probably noticed that some of them have simple uniform diameter pipes coming out of the engine while some other bikes have very different-looking pipes with large bulges and great variations in diameter.

A two stroke exhaust pipe has a weird shape with greatly varying diameters and a large bulge in the form of the expansion chamber. You can only find it on two-stroke motorcycles and never on four-stroke motorcycles.

To understand why we need these pipes we must first observe the two stroke engine in a bit more detail. Unlike a four stroke engine a two stroke engine has no camshafts or valves, it’s cylinder head is essentially just a cap. Despite this simple construction the two stroke manages to fire during every single engine revolution which means that we have a combustion event every 360 degrees of rotation whereas in a four stroke we have a combustion event only every 720 degrees of rotation. All of this means that a two-stroke is capable achieving a better power-to-weight ratio than a four stroke.

When the piston first uncovers the exhaust ports and the blowdown phase begins the exhaust gas of course rapidly bursts out through the tiny opening. This of course creates a loud powerful sound and as we know sound is a pressure wave so we get a pressure wave coming out of the engine going through the exhaust pipe. Various explanations you might have encountered may have used terminology such as exhaust pulse or combustion pulse or similar and while these are not necessarily incorrect and can help you visuallize things they become useless later in the explanation. What comes out of the engine when the exhaust port opens is in fact a sound wave which is a pressure wave. Here you can see an image shot using a special photography method that shows the end of an exhaust pipe releasing exhaust gas into the atmosphere. Here you can see the pressure wave which is only later followed by the actual exhaust gas.

So the pressure wave is traveling through the pipe. It remains pretty constant through the initial uniform part of the pipe. After this, it reaches the diverging or the expanding section of the pipe. So what happens here? Here we have a change in the medium. Or medium is gas and if the pipe diverges our volume increases which means that the molecules of the gas in this space are further apart, in other words, the gas is less dense here. And whenever a wave encounters a different medium or a change in the medium itself the wave or part of the wave gets reflected back.

You have probably experienced echo at some point in your life. Echo is simply a sound wave that got reflected back as it encountered a different medium. The sound wave travels through air and reaches a wall. A wall is a different medium and so part of the wave gets reflected back.

But here’s the important part: When moving from a medium of higher acoustic impedance to a medium of lower acoustic impedance part of a longitudinal wave will get reflected back AND it will also undergo a phase change.

When that longitudinal compressive wave encounters the diverging section of the pipe it transitions from a higher density gas to a lower density gas, or from a medium with a higher acoustic impedance to a medium with a lower acoustic impedance. When this happens part of the compressive wave continues through the pipe but part of it gets reflected back to the cylinder as a negative pressure wave moving in the opposite direction. This negative pressure wave reduces pressure of the gas as it travels back to the cylinder, and of course it reduces pressure inside the cylinder when it reaches the cylinder.

So there you have it the shape of the pipe allows us not just to suck in more air and fuel into the cylinder, but also keep that same air and fuel from escaping the cylinder. That's great, but we still have a problem. As you probably know the engine operates at a very wide range of rpm anywhere between 800 to 10.000 for engines like this 300cc single cylinder two stroke. But different engine rpm means different piston speeds and thus different duration of the intake, compression, combustion and exhaust events inside the engine. On the other hand the speed of the sound waves through the exhaust pipe is more or less constant…this means that we can only perfectly match the arrival of the sound waves at the cylinder over a small narrow rpm range

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00:00 The Problem with Two Strokes
04:25 Wave Basics
09:10 How It Works
17:33 Let's Hear it in Practice

#d4a #2stroke

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Just a few days ago news has surfaced on the internet that Porsche has patented a revolutionary new six stroke engine which according to them has the power benefits of a two stroke engine but the durabtility and emissions cleanliness of a four stroke engine.

As you probably know traditional four stroke engines which powers virtually every combustion car, truck or motorcycle on the roads today gooes intake, compression, combustion and exhaust.

Porsche new design adds one more combustion and more compression stroke into the mix and so the new engine goes: intake compression combustion compression combustion exhaust.

This relies on 100% existing technology. Gears, rod, crank, piston. Even the ports which are known as scavenging ports are ancient. Btw, this very arrangement with ports on one side and valves on the other is known as uniflow scavenging. Because the flow goes in a uniform direction through the cylinder. And this is very common on two stroke diesels in ships and locomotives. The six stroke also don’t make any serious problems for the camshafts. Instead of rotating at half the crankshaft speed, the camshafts will now rotate at one-third the crankshaft speed, so we just need a slightly larger cam gear and we also need an additional lobe on the exhaust come and that’s pretty much it, nothing complex. So there are really no novel mechanics in this which means that it doesn’t need heavy investments into research and development to get it to market.

It does make more power than a traditional four-stroke. If we observe the first 720 degrees of rotation we can see that we get only one combustion event, just like a traditional four-stroke. But if we observe the next 360 degrees we will see another combustion event starting at 720 degrees of rotation. This does not happen in the traditional four-stroke until we reach 1080 degrees of rotation.

So if we observe let’s say 7200 degrees of rotation, the traditional four-stroke will perform 10 combustion events. The six stroke will perform 13.34 combustion events. So that’s 33.4% more power than a traditional four-stroke. Now, it’s definitely not in two-stroke territory because a two stroke will perform 20 combustion events in 7200 degrees of rotation and that’s 20 equal, proper combustion events. Remember, on the six stroke, every other combustion event is a mix of exhaust gas and air and fuel which means that we’re probably not looking at a power increase of 33.4% but likely something closer to 25%. But 25% more power with existing technology and emissions cleanliness and durability of a traditional four stroke is still a very significant improvement and a very clever and rational way towards more power.
Something else this makes possible is to run very high boost pressure and still be relatively emissions-friendly. To run something like 3 bar boost pressure which is 45 psi you need to run very very rich. You make crazy power but you’re also sending some unburned fuel into the atmosphere which means crappy emissions. But in a six-stroke we would not send all that unburned fuel out. We would send just a bit of it out and the rest would be burned during the next combustion stroke. So potentially, big power and government approval.


But why would Porsche patent this now if sales of new combustion vehicles will be banned starting with 2035 in the EU and I believe some other parts of the world.?

Well, here’s the thing, the EU is not fully banning sales of new combustion vehicles starting with 2035.
On the 25th of March of 2023 EU reached an agreement with Germany where it was agreed that sales of and registration of new ICE vehicles will be permitted after 2035, provided that those vehicles operate only on carbon-neutral fuels.

So what this patent means is that Porsche is taking preventive measures to ensure that it can produce high-power and emissions-friendly engines that can still fit inside the back of a 911 in case e-fuel production ramps up before 2035. By patenting this design Porsche ensures that nobody else can implement it without paying fees to them.

So will we see this engine in the future? Well, if e-fuel production does actually ramp up, I think it’s likely that Porsche will greenlight some sort of project. Will e-fuel be expensive? Probably. But I doubt that’s a major problem for Porsche buyers.

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00:00 How it works
08:34 Benefits
14: 34 Drawbacks
19:01 Why now?