3-Cylinder, 4-Cylinder and 5-Cylinder engines explained. Why cylinder counts matter

Have you ever wondered why 3 and 5 cylinder engines exist? This video covers that and more! 5-cylinder engines have been used for some time in Volvo models like the C30, S40, V50, S60, V60, V70, S80, XC60, XC70 and XC90, but also by GM in vehicles like the baby HUMMER and Volkswagen and Audi in various models. This decade the new odd number is three. With the new 1.0L Ford Ecoboost in the 2015 Forst Fiesta SFE and the 2015 Ford Focus SFE 3-cylinders are coming back to the mainstream. You'll of course also find 3-pots in the Smart ForTwo, Mitsubishi Mirage and the MINI Cooper. If you've wondered what's going on under the hood this video is for you. I'll talk about exhaust gas scavenging, turbochargers, efficiency and combustion overlap. Statistics powered by ChannelMeter http://channelmeter.com

Comments

1. 6:06 Claims a turbo engine is more efficient than a comparable NA engine...yet FI engines generally have WORSE BSFC maps than NA!
   I'd say a turbo engine is only "more efficient" than a NA engine if you spend most of your duty cycle OUT of boost. If you're going "flat out" (underpowered engine and/or towing), the NA should beat the FI.
2. Intersting... but starts badly since most 4 cylinders have 2&3 rising together to avoid longitual rocking, firing 1342 not 1234
3. Based on how informative this was. You should have at least a million subscribers.
4. Allright! Now i get it! Those bi-turbo volvos T6. Thanks
5. nice explanation 👍👍
6. I think 4-cylinder engines fire 3-4-2-1 not 1-2-3-4!
7. my accord is a three cylinder.. and a 6 cylinder when i need it to be.
8. I dont really get how the number of exhaust-gas-pulses depends on the number of cylinders - why does 2 cylinder engine have 3 pulses shown? And 4 cylinder 5 pulses? I thought there should be as many pulses as there are cylinders...
9. The number of power pulses per revolution does contribute to
   the feel of the power delivery. But is a really really small part of the smoothness.
   Vibration caused by the reciprocating mass of the engine causes almost all the
   felt vibration or "smoothness". A 5 cylinder engine is inherently unbalanced.
   They are vibration monsters without big counter balancers. A flat 4 engine is
   one of the smoothest running engines there are because they are inherently balanced.
   This is why Volvos eat motor mounts. Think of it this way you have a 3
   cylinders going up and 2 coming down at the same time the 3 cylinders going up
   have more mass so they what to push the engine in the opposite direction. With
   a 4 you have 2 up and 2 down so the net force is zero. Now let’s say you grind
   the crankshaft to time the motor so that all the pistons are equally spaced. Let’s
   take the center for mass for the engine at its center and balances each side
   out. Well now we have a problem you can’t split the center cylinder down its
   center so now you have one cylinder that will always be unbalanced causing
   vibration. Because there will always balance issues because the center or mass
   of the engine and the reciprocation parts are not equal. You can’t divide 5 by
   2 and get an equal number.
   
   So in short you kind of have an idea of what is going on but
   are missing the biggest part of the equation.
10. what about noise ?
    i noticed that 3cyl. in BMW 1-Series is loud at `2000 RPM
11. 1:50 but why are no or close to no sequential 4 cylinder engines on the road? wouldn´t that make the engine run smoother, having one powerstroke in each stroke-chain?
12. Very nice, can you accommodate Motorcycle cylinders in your next video, which doesn't have turbo charged (from manufacturer) yet.
    Question: around 2:38, when explaining about 4 cyl, you mentioned 4-cyl are not well-balanced, can you please elaborate that point.
    
    Hope to see another video with V- and L- shaped desmo engines for motorcycles without turbo.
    Thanks in advance.
13. THank you that was awesome Alex! I finally understand!Great explanatory video animation. I loved my 5 cyl Audi 90 and Turbo Volvo 850R. Now I know why.
14. Gets me wondering why they gotta make 3 cylinder engines so small i.e. 1,0 1,2 and 1,4 cm3
    Wouldn't it be more efficient but incredibly strong to make one at the larger 2,0 cm3? I only see 4-cyl 2,0 liters
15. RIP Volvo D5 /:
16. Talk about B38 and B37 BMW engines!
17. lets talk about an older jeep. 1,3,2,4.
18. 6:51 the only factory turbo 2 i can think of is the Polaris RZR turbo and the Maverick Turbo.
    
    i wonder how they got past this problem
19. turbin.. haha
20. LOL, "turban" = headcloth for Middle-easterners.
    "TurbINE" ("tur BIN" -- long-i sound, as in the i-sound from "brine" or "buy") = set of spinning blades driven by a fluid, as in a turbo.
    2nd set of spinning blades is not a turbine, but an impeller or pump or fan.
    
    Thanks for the video, though. Wrong pronunciation aside, it does explain well.