Volkswagen’s New Engine Cycle – The ‘Budack’ Cycle

Volkswagen’s New Engine Cycle – The ‘Budack’ Cycle

Hello, everyone and welcome we are inside of the 2018 Volkswagen Tiguan. This is Volkswagen’s first model which is running their new EA888 engine running the new Budak cycle, this new engine cycle which Volkswagen has developed it was named Budak cycle by Volkswagen after their powertrain engineer who developed it. Now this cycle is basically a variation of the modern Atkinson cycle, which is a variation of the Miller cycle without a supercharger, so what does all this mean? Well that’s what we’re gonna get into in this video. How does this engine work? Why is it more efficient? That kind of thing. So in order to understand that we need to understand the Atkinson cycle, and the modern Atkinson cycle what it is is during your intake stroke, everything happens as normal your intake valve opens your piston moves down it pulls in that air fuel mixture now during the compression stroke you leave that intake valve open for a short duration, so you’re pushing out some of that air some of that intake charge and what this does is it lowers your effective compression ratio so now your compression ratio is smaller than your expansion ratio because your expansion ratio has remained the same that never changes now by having a lower compression ratio than your expansion ratio. You’re able to extract more useful work out of it so the whole idea is the piston has a longer distance to travel down and expand outward than it is compressing that gas so more of the energy from combustion is turned into useful work the ultimate goal is that the at the bottom dead center of the Atkinson in cycle, what happens is you’re at atmospheric pressure that’s the ultimate goal. So that means you’ve turned all the available heat and pressure from combustion into useful work the Budak cycle, the cycle which Volkswagen has developed is basically the same thing except instead of opening the intake valve for a longer duration you’re closing that intake valve sooner so during the intake stroke you’re going to close that intake valve before that piston reaches bottom dead center now this is effectively doing the same thing you’re reducing the amount of air that you pull in and as a result your compression ratio is less than your expansion ratio and because of this of course you’re going to have greater efficiency so the specific output of the engine goes down when you’re running this mode, but the efficiency goes up, so it’s great you know when you’re cruising on the highway when you’re at low loads and Volkswagen has a solution for when you want power, so when you do want power. There’s a cam lobe switch, so there’s this little pin that forces the cam to a longer duration profile and actually a higher profile so you open the intake valve more and you open it for a longer duration and so that’s for this power cycle when you you know you put your foot down you want full power from the engine it gives it to you and it switches over to you know the normal Otto cycle that most engines out there are running so they do have you know a pretty cool visualization of this 3D model and so I’ll try to put these two intake strokes side-by-side and hopefully you can see the difference you know the intake valve running the budak cycle closing sooner than you know when you’re just running the traditional Otto cycle and you know you want to make more power for that version. So pretty cool that you know it’s able to switch between these two different modes it’s not you know the most groundbreaking thing ever. They’re just you know it’s a it’s a different take on the Atkinson cycle, which is a way of increasing fuel economy so cool they’ve taken another approach to it and you know come up with this clever solution to differ the expansion ratio from the compression ratio. So has this engine cycle change been an effective means of increasing fuel economy? Well it certainly has improved from the previous generation Tiguan but you’re still only getting 27 miles per gallon on the highway Even if you get the all wheel drive version or the front wheel drive version both of them getting 27 miles per gallon on the highway which for this segment you know certainly isn’t class-leading the Honda CRV the Mazda CX-5 the Subaru Forester all of those you know able to achieve the low 30 mile per gallon range on the highway so they are able to do better than you know this engine cycle. This is a fairly heavy vehicle so that probably plays a big role in its fuel economy rating it is cool that they have improved it although you know compared to the competition they’re not exactly at the top. If you guys have any questions or comments feel free to leave those below. Thanks for watching!

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  1. On long trips my 1.6 turbo subaru got about 40miles pr gallon with 4people in the car and luggage. (Summer miles) with rain on the same trip I got about 38miles per gallon. But this is a low wagon.

  2. Doesn't closing the input valve earlier make the cylinder work against external atmospheric pressure, i.e. trying to pull a vacuum? Wouldn't waste power?

  3. Thats why i'm getting really good gas mileage….I feather the throttle a lot so the numbers i get are in the mid to high 30s mpg. I even got 40 at one point. Throw me into the city though, and the mileage drops to 24.

  4. With sigma six the closer you are to 100. The more effort it takes to achieve it. Similar to traveling at speed of light. It takes a lot of energy to travel up to speed but of light. I also believe that there is beyond the speed of light just like hypersonic speed. More to come.

  5. If they think that this is new and innovative, it honestly just shows how ahead of their time Honda and their vtec engines were.

  6. My immediate thought is that the Atkinson cycle is inherently more efficient than Budack cycle because the Budack cycle is pulling against vacuum when the intake valve closes and the piston is still traveling down. But, as I am typing this, I guess maybe the Atkinson cycle might have an analogous issue when the piston has to force the intake air back into the intake before the valve closes.

  7. Why did they make another cam profile, instead of making the VVT cam phaser close the valve earlier? No new camshaft, just a program change.

  8. Something I'm particularly fond of is Freevalve technology, which uses pneumatic valve control to ditch the camshaft altogether. One of the greatest benefits of a camless design is that your engine can be fully programmable.

  9. People in the comments being utter assholes. This is not the opposite of vtec you idiots. Vtec changes the profile to compensate for increased RPM. This changes the profile to achieve a change in the effective CR, which is always the same in Vtec.

  10. This cycle only makes sense to me when there is lower than atmosphere pressure under the pistons or there is a pressure filling (turbo/supercharger).

  11. Always been able to get ahead with engine technology and performance it is time we go electric and use the Rodin coil for electric vehicles

  12. Have VW/Audi incorporated multi port fuel injection? Or are they still running direct port injection? Have they address carbon fouling on intake valves?

  13. Yet another case where we're using fancy efficiency-improving tech to make vehicles bigger with the same fuel economy instead of the same size or smaller getting amazing fuel economy. 40 or 50 years ago cars were doing better than this! But nobody wants small cars, or cars in general, anymore… I have thought of, maybe heard of, similar concepts to this, taking this all a step further would be with completely variable valve timing – maybe Koenisegg's camless design, or something that dumps oil out of a hydraulic lifter of some sort – the intake valve could be closed at any point in the intake stroke, or even not opened at all. Engine wouldn't have a throttle, control would be purely on how long the intake valve is open, it would just be briefly cracked open for idle, not opened at all for coasting, opened for part of the stroke like this for part-load cruise, and held open past BDC for full power, the equivalent of a performance cam. It does make sense to close the valve early, before BDC, rather than holding it open past BDC to push some back out on the compression stroke as the Miller cycle does – I have to imagine sucking air in then pushing it right back out must incur some efficiency losses versus not sucking it in in the first place.

  14. Did they fiddle the emissions test results on this one too? Let's call it the bullcrap cycle and be done with it.


  16. That's what the Caterpillar truck engines did…. then they went out of buisness because they weren't reliable and everyone hated them

  17. There’s this pin….. and then there’s no pin, it’s now shrapnel floating around in your engine… good grief. I’ll stick with my 7.3 powerstroke doing 22mpg and 550k kms…

  18. Do the injectors close soon as well with the valve, otherwise wouldn't it just leave fuel air mix in the intake? Just to waste.

  19. As I recollect, the Prius Atkinson cycle engine has a blower. If VW can achieve same w/o blower, that’s significant.
    BTW, the ~1943 Lycoming XR7755 had a two speed cam. I think it shifted axially between take off & cruise. Many old ideas are reborn w/ advent of new tech, like microprocessors.

  20. Engine design begins with thermodynamic analysis. The Budack, Atkinson, Miller cycles are distinct when plotted as pressure/volume or as temperature/entropy and thus named individually.
    BTW, compression ratio is geometric- it’s the same throttle open or closed. What is thermodynamically relevant is pressure & pressure ratio.

  21. Let's mix an overcammed sbc, vvt, cut it in half and pretend we came up with a new engine cycle that equates to mediocre fuel efficiency. VW wins again!

  22. Wen Siemens Anlage nicht bauen kann ohne Ende andere in Welt.

    Schnell rüber zu Erdgas nicht mit Nordstream II aber mit weltweit ca.
    1000bar CNG Kugeltanksystem mit ISO (See) Container Rahmen wen verdunden gebracht & geholt statt gekühltes LNG Schiff, LNG Terminal

    und 50bar Leitungen bis zu Haus !


    Import von Steinkohle Nr. 1 China Nr. 2 Indien Nr. 3 Japan Nr. 4 Südkorea Nr. 5 Taiwan Nr. 6 BRD

    dazu Nr. 1 Braunkohleproduzent.


    Produktion Steinkohle Nr. 1 China 49,3% Nr. 2 Indien Nr. 3 USA Nr. 4 Australien Nr. 5 Indonesien


    Export Steinkohle Nr. 1 Australien Nr. 2 Indonesien Nr. 3 Russland das so mehr Öl & Gas verkaufen kann wie mit Atomkraft in Russland usw.

    Fördertop Steinkohle in Welt war erstmal 2013 bis 2016 gefallen wegen China das aber wieder viel in mehr Produktion dort investierte.

  23. Thats totally bollocks.. Can anyone imagine these modern engines running more than 100.000 km without falling apart? This isn't Innovation, its making simple things more complex so you can charge more money because shitty engines are "New"

  24. E molto istruttivo .peccato che molte spiegazioni tecniche siano
    in lingua inglese ( in teoria meccanica sono molto Ferrato !!!!)

  25. It's 2020. Everything is DUNG ! This engine will be a liability after it's warranty expires, while a 1908 Ford Model T can still be rebuilt…

  26. Whats the point? Aren't all the cars being dropped for electric cars? Plus the petrol in USA is a very low octane rating isnt it?

  27. does that not cause slight parasitic losses due to the piston putting a vaccum on the cylinder? Also what makes this more efficient than the Atkinson cycle ?

  28. When you say "cycle" it leads a person to think it has something to do with the engine's.. uh..
    This just in:
    Brand new vanilla ice cream! Exactly the same, but we cut the vanilla by 2.72%

  29. BMW is using this on their 1250GS motorcycle except their intention is to use a torque friendly cam duration at low rpm and switch to a high rpm cam duration when past 6000 rpm I believe.

  30. Please tell me there are Lao ppl out there that thought VW was using fermented fish paste when you read 'budack'

  31. So we want a low compression engine with long/short inlet valve timing. Do I note bowl piston? What if we return to side valve engine with limited power output adequate for today’s road conditions ? This would be simple and cheap to construct use less material and the back room boys can shave little bits off the cylinder edges and put swirl bumps in the heads as in days of yore and say they have invented something new. Everybody would be satisfied especially if you put it in a Chelsea tractor for the school run!

  32. What ever you make..the effiency isnt higher than % 25 in lab conditions..practically you get just only %10 energy of burned fuel..what does it mean? otto engines isnt suitable for any transport..

  33. The holy grail will be the replacement of the entire mechanical chain/phasers/cams valvetrain with digitally actuated valves. Oldsmobile had a solenoid valve system in development decades ago, now we need modern engineering to carry it over the goal line.

    Imagine dynamic engine tuning that can drink wisps or air and fuel at cruise, but able to flood the cylinders with both for ultimate performance. Even better, configured to make adjustments on a per cylinder basis, allowing the ramping of effected parameters rather than a whole bank changing at once.

  34. Why don‘t they use „freevalves“? (like koenigsegg) Then the mechanical shifting between modes becomes unnecessary and you could electronically choose the optimal mode for any load situation. Too expensive? Patent problem?

  35. Does anyone know what turbo’s are being used on these 2.0 EA888 3B engines? Is it an IS20 or not?. I’ve just ordered a polo GTi with this engine, however It’s very hard to find what turbo is used – many thanks!

  36. Thank god I will live to see people stop wasting their energy on making a dead technology like combustion engines more efficient. At this point it's like they're trying to create upgraded tuned zeppelins instead of planes

  37. Hi bro.,
    My question is in budack cycle it closes the intake valve early then otto cycle, due to its early closing is it effected on engine parts like valves,spark plug etc.
    because piston is still moving downward direction and there is no opening for air suction, then it will create some vaccum in the chamber. that vaccum effect on life of Intake/output valve's life or any other part

  38. EPA estimates are a lot lower than what publications like Car and Driver have received, and lower than I have experienced on a rental. I've got 34MPG on highway on the last one I drove.

  39. The marketing department says to the engineers give us something different to market, anything! and they come up with "something", anything that the others are not using. Nothing special or technically advanced because in a few short years they will need another "something". The Marketing department "Breakthrough, radical, cutting edge, quantum leap, blah blah and blah blah blah." Almost forgot, top Honchos to Engineers "Make sure it holds together until just after the warranty runs out."

  40. Before I even started this vid I was thinking 'this is yet another Atkinson cycle, isn't it?'

    Yup I was right. Nothing special…

    What happened to electromagnetic valves, six stroke engines and ducted diesel injection?….

  41. a lot of breakdowns planned for these Veedubs… high sulphur fuels that is found in most markets will require more frequent oil changes, most owners not wanting oil changes because they were told at sale time services a longer apart. What they should do is us the current camless engines. running piezo electronics that open a valve with spring return like BMW did back in the early 2000s on a 318i test car. very reliable and cost effective and an adaptive camshaft map. should be able to be a very volumetric efficiency across the whole rev and load range

  42. СИСТЕМА ИЗМЕНЕНИЯ ФАЗ. эта система используется с прошлого века🤣 АМЕРИКОС ДЛЯ ТЕБЯ ЭТО НОВИНКА????🤣👍

  43. My neighbor had a VW Tuareg. He had an Isuzu SUV before. The Tuareg (according to him) was "the most unreliable vehicle he's ever owned" – and extremely expensive to service and repair. The Isuzu, on the other hand, was "the least expensive to maintain and most reliable vehicle he'd ever owned". I bought it from him when it was 12 years old and I ran it for another 13 years. It cost next to nothing to maintain.
    My neighbor spent $35,000, on the VW, over the next five years. (New engine, new auto transmission, new catalytic converter, multiple electronic and brake issues. Other people I know, who have owned Tuaregs have told me similar horror stories re. reliability and overpriced spare parts.
    Reliability is everything, unless you're only going to do city driving. .
    A slow revving, simply designed, unstressed Diesel engine that is cheap to service is a no-brainer. At 30mpg, over 30,000 miles, the fuel cost is about $3000. 25mpg, equates to $450 _extra_. ie no big deal.

  44. Then adjust/shorten the duration the valve is open and call it a different cycle??? Really general public? Really have a spine.

    So that logic I swap cams (to a smaller cam) to which the intake valve closes sooner can I call it a different cycle name now.
    And the public eats this up???? Wow

  45. Uhmnnn. Fiat multi-air anyone? Or do we just kiss German and Japanese ass even when their system is more prone to failure.

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