Why Not to Buy a 4 Cylinder Engine Car

today we're comparing the inline 4 engine versus the boxer 4 engine both are internal combustion engines and both have four pistons but each engine layout is quite different so which type performs better it's smoother easier to maintain and sounds better and why do subaru and porsche insist on the boxer whereas other car makers prefer different engine layouts come with me as we compare the inline four versus the boxer four let's briefly start with the basics one of the most common engines we see today is the inline four-cylinder engine known as an inline four i4 or straight four it's mechanically simple just one cylinder bank with four cylinders mounted in a straight line along one crankshaft the pistons sit upright and move up and down on the other hand a few well-known car makers namely subaru and porsche prefer the boxer four engine layout instead a boxer four engine is also a four cylinder piston engine but it has two cylinder banks lying on opposite ends of the crankshaft each pair of opposed cylinders moves inwards and outwards the same time that's why i call it boxers like a boxer with boxing gloves for a more detailed video check out my video on different engine types both the inline 4 and boxer 4 are based on the same four strokes intake compression power and exhaust but because a different layout the inline and the boxer have a different firing order and therefore differ in engine balance here's what i mean if you count the cylinder from the front and accessory side of the rear flywheel side you see the inline four fires at one three four and two whereas the boxer four fires at one three two and four in each engine design the primary forces are identical and cancel out but the secondary forces differ between the two engines the secondary forces result from a difference in piston speed during the top half of crankshaft rotation in other words 90 degrees before and after top dead center versus the bottom half with the inline four the pistons reach the top or bottom of the cylinder and the secondary forces point outward this leads to vibrations and less balance that's why the inline four often needs balance shafts to cancel out vibrations but with the boxer 4 the pistons point away from each other this means the forces balance out and that's the reason why the boxer 4 is smoother than the inline four but this doesn't mean the boxer 4 is perfect either the pistons in a boxer aren't perfectly aligned since they don't sit directly across from each other so this can create a torque that tends to want to rotate the engine along its vertical axis with rocking motions ever wonder why a boxer 4 has a distinct burble in fact owners of subarus have come to call it the boxer burble well actually particular tone comes from its unequal lengths headers the exhaust design usually pairs well with the engine package and also happens to create the burble sound that fans have come to recognize and love let's compare the pros and cons of the inline four and the boxer four the advantage of the inline four is that it's small and compact so it can fit easily into most engine bays it's light in weight because you only have one exhaust manifold it's simpler and less costly to make because there are fewer moving parts it's also simpler and less costly to service to fix because the cylinder head is the highest point so it's easier to access and fix spark plugs in the valve train so you can see why most major car manufacturers love it and why the inline-four is one of the most common engines on the road today but the inline-four also has its disadvantages for example the secondary forces are not balanced so this limits the size of the engine that's why you rarely see an inline four-cylinder engine that exceeds 2.5 or 3 liters large 4-cylinder engines often require balancing shafts to cancel the vibration caused by the secondary imbalance and because the inline sits tall and high it has a higher center of gravity than the boxer for now let's compare that with the boxer fork from an engineering perspective the boxer is the choice if you want smooth acceleration and performance as i touched on earlier the reciprocating pistons they reciprocate horizontally in a boxer so they cancel out vibrations the primary and secondary forces are well balanced so you'll get less vibration and smoother acceleration and of course since the pistons of a boxer engine like black contrast that to an inline engine where the pistons stand tall and move up and down the boxer has a lower center of gravity which means much better handling dynamic driving experience and stability at high speeds in the corners also less weight on the crankshaft means less power loss to rotational inertia another advantage with the boxer is improved thermal efficiency because of its layout and construction coolant flow is better which means heat gets dissipated more effectively but the boxer has downsides too for starters it's more complex than the inline engine so understandably it's more expensive to make also servicing the boxer engine is technically more challenging since the packaging is tight and many of its components are harder to access on some engines you have to drop the engine out of the vehicle to do any type of serious work and it's not uncommon for boxers to have issues with oil leaks and then you have to address the issue with size the boxer 4 engine is wider than an inline 4 since the cylinders lie flat and are horizontally opposed so fitting a boxer into a front-wheel drive car is more challenging by the way contrary to popular belief the boxer engine was not the brainchild of ferdinand porsche actually it was patented by carl benz who built his first one in 1897. it was called the ben's contra engine and it was used in road cars like the benz faten and the benz ma lord but production of the engine ended in 1902 and benz never used the boxer engine again did you know that ford once toyed with flat twins in the early days chevrolet did too for a time take for example the famous chevrolet corvair which came off the flat 6 engine and volkswagen initially lodged its company based on an air cooled flat 4 engine when they introduced the original beetle and the first horse 356 came with a boxer engine which output 35 horsepower that was back in 1948 but today porsche and subaru are the only large car manufacturers to continue equipping their engines with boxer engines porsche is the only car maker that uses the flat h-shaped opposed piston boxer engine and subaru is the only car maker that uses the boxer engine exclusively in their entire lineup did you know that every subaru model ever made since subrose start 1953 has had a boxer engine and they don't have any plans to change it ever wonder why subaru has stuck it out with a boxer and whether it might change since more plug-in hybrids and electrics are coming to market well first subaru values smooth acceleration the boxer's lower center of gravity means a more dynamic driving experience for subaru's taller all-wheel drive cars with a higher ride height take for example the forester the outfit and the crosstrack the boxer also ensures that subaru's performance sports cars like the wrx and wrx sdi remain stable at high speeds when cornering but it's more than that another core benefit is safety subaru's boxer design helps reduce damage in a collision since horizontally opposed engines are low in overall height in the event of a frontal collision the engine gets pushed under the floor not into the passengers so this reduces the risk of injury here's a question can you turbo charge a boxer well yes indeed let me give you some examples the subaru wrx it features a 2-liter turbocharged boxer 4 under the hood it generates 268 horsepower and 258 pound-feet of torque it can reach 60 miles an hour in 5.4 seconds there's also the subaru legacy with this 2.4 liter turbo boxer for it we're talking 260 horsepower and it's fuel efficient with 32 miles per gallon on the highway the most powerful subaru turbo option is the 2.5 liter boxer 4 in the subaru wrx sdi 310 horsepower thanks to a new high flow intake and low restriction exhaust it reaches 60 miles an hour in 4.9 seconds porsche fans have their favorites too you have the porsche 17 cayman which offers the 2-liter flat 4. actually porsche did something unconventional with this one previously it had a standard flat six but then they downgraded it to a four cylinder and turbo charged it it's incredibly powerful outputting 365 horsepower and 317 pound-feet of torque by the way a fun side story most people assume the sports car was named after the cayman islands but actually porsche said the sports car was named after a small marine crocodile species the caiman the same one that the cayman islands was named after but don't think that performance and speed are all dependent on the turbocharged flat 4 a turbocharged inline four engine can do a lot too a few years ago in 2017 the honda civic type r smashed the nurburgring lap record for front-wheel drive cars it clocked a lap time of 7 minutes and 43 seconds beating cars like bmw m5 chevy corvette z06 c5 and porsche cayenne turbo s its engine turbocharged inline four made 306 horsepower and 295 pound-feet of torque if you missed my video on the honda civic type r check it out well just two years later in april 2019 the renault mcgain rs trophy r set a new all-time record for the fastest front-wheel drive production compact car ever at nordschleife of the nurburn ring the new record time seven minutes 40 seconds and that was accomplished with the 1.8 liter turbocharged inline four that spun out 296 horsepower this toppled the honda civic type r 2017 record by three sec both the inline four and boxer iv have the same number of pistons but other than that pretty much everything else is different if you want easier and cheaper cost maintenance then you'll probably appreciate the inline four more if sound and smooth ride is your priority then you'll probably like the boxer more but now you tell me what do you think in line 4 or boxer 4 which do you prefer please comment below and share your opinion if you enjoyed this episode please subscribe to my channel for more car technology and history videos thanks for your support

Channel: Scotty Kilmer

Views: 345,628

Keywords: auto, auto repair, car, car diy, car repair, cars, diy, how to, mechanic, repair, scotty kilmer, car review, inline engine, engine, inline, inline car, inline 4, inline 4 cylinder engine, car buying, how engines work, engine explained, explained, how it works, which is better, car vs car, engine vs engine, 4 cylinder, diy car, boxer engine, boxer, boxer engine car, boxer engine explained, how boxer engines work, inline engine vs boxer engine, i4 vs boxer engine, i4 engine car

Id: viVYg1cCAAg

Length: 10min 17sec (617 seconds)

Published: Fri May 28 2021