Car Tech 101: Understanding engine configurations

now I would need a miniseries to cover all the pros and cons of the different engine configurations but each is good at or bad at and even then no two engine geeks on earth really agree with each other let alone me so we're not going to go super deep into that instead I'm going to lay out and visualize for you how each major engine layout is done and give you some conventional wisdom on what its benefits are okay the inline engine is perhaps the simplest most basic and most common this is an inline four one of the Ford EcoBoost motors and this gets its name because the cylinders are arranged in a line if you look down from the top inline four is a very common inline sixes are very common these engines are known for being very compact lightweight simple inexpensive to build relatively and because these engines are so compact and they're almost square if you viewing from the top you can mount them either way longitudinally running the length of the car or transversely running across the car and many different cars use one or the other now the V engine you know mostly has V sixes and v8s these days although you can go all the way down to V twins and motorcycles v4 Saab launched afford have all made those back in the day but the conventional v8 looks like this here's your ford shelby v8 for example and there's your v right there in the front you've got one set of four Pistons and cylinders that are laying over this way another set laying over this way it's kind like you took two in-line fours married them to one crankshaft and just tilted them apart so they could live in one space the key here is that you're fitting a lot of cylinders into a relatively compact space especially when you get to higher cylinder counts like six or eight or ten this v8 if you made it into an inline eight would be like this long it wouldn't fit in just about any car out there but by nesting it in a V configuration you gain some width but you lose a lot of length the other key nuance around the engines this varies by maker is the angle of this V are those cylinders almost touching are they laid out much further apart the angle of that V is one of the secret sauce items for engine designers v8s and v6s are also known as being inherently pretty well balanced and of course because they pack a lot of cylinders into a smaller space they do get a lot of power they're known as high-performance engines in most cases the W is in many ways a derivation of the V the most common example these days is the VW Group design that includes a w8 in some Audi r8 a w12 and some Bentley's and a W 16 in the Bugatti Veyron now visualize this w as a pair of V engines that are mated together to drive a single crankshaft and in this VW design each of those V sets of cylinders are nested so they overlap a bit if you run an imaginary line sort of down the set of them this W has the V engines benefits of putting a lot of cylinders in a short space but also its own benefits of putting a lot of cylinders in a narrower nested space now the rotary engine in the car world this really means the Wankel rotary engine that has been used in Mazdas for several decades inside an egg-shaped combustion chamber there's a triangle-shaped rotor that turns or rotates with the combustion in the spaces that it creates as it spins and geared down the middle of that rotor is the shaft that turns and feeds the transmission now because Wankel rotary don't have a bunch of pistons and other parts that are jerking up and down violently changing direction every split-second they can spin at higher rpms and do so smoothly without self-destructing on the downside they've long struggled with highest fuel consumption and emissions and a struggle for a lot of power largely due to the trickiness of ceiling those three tips of the rotor as it sweeps around the inside of the engine and it's terrain of spark plug ports and intake and exhaust openings now let's talk about a flat engine also there's a boxer or a horizontally opposed engine this is one of the most famous right here in a Ferrari Testarossa it's a flat 12 you've got six cylinders on each side as you can kind of see there and on the other side are six more and they are exactly flatly opposed to each other 180 degrees apart the point here is you've got a very low engine because the thing sticks up it can be a low motor that sits low in the car giving you a lower center of gravity great for performance and cornering it's also an engine that is good if you're trying to package the body low for a low sleek design take a look at let's say a Subaru BRZ they were able to get a low center of gravity and alone knows because they've got a flat engine in there these are called boxers because they have pairs of cylinders Pistons in them that are punching together at one time in any given direction flight engines are also known for being very balanced because their pistons and connecting rods are literally in exact opposition things tend to just work themselves out and not have a lot of weird vibration or moments that have to be counteracted with other apparatus like counterweights these are engines that are known very well from Subarus they have fours and sixes that are their famous boxers and of course the Porsche 911 is a flat 6 more car tech demystified right now at CNET on cars comm click on car tech 101

Channel: CNET

Views: 677,579

Rating: 4.9395185 out of 5

Keywords: Car Tech, CNET On Cars, Brian Cooley

Id: y__rjR0woBM

Length: 5min 44sec (344 seconds)

Published: Tue Feb 10 2015