1. Perfectly vertical
   At a 45-degree angle
2. Flat or horizontal
   At a 60-degree angle

While not a highly conventional design, the Boxer engine is used in some four-cylinder cars. Its name comes from the fact the pistons look like a boxer's gloves as they move in and out.

1. 1902
   1922
2. 1895
   1917

Despite what many people think, the first car with a four-cylinder engine was American, the Buffum Four-Cylinder Stanhope. It looked more like a horseless carriage than a car, but marked an important step forward in automotive technology.

1. Four-banger
   Four squash
2. Four-hopper
   Foursie

Most people agree that this slang term for four-cylinder engines started with the hot rod movement. There's disagreement about why it was first used, but the term has stuck around for a long time.

1. Sports cars
   Pickups
2. Motorcycles
   SUVs

There are a few cars with a V-4 engine, like certain Lancias, Fords, and AMCs. For the most part, this engine has been popular for higher-powered motorcycles, although cooling the rear cylinder bank can be a little problematic.

1. 1-3-4-2
   1-2-4-3
2. 1-3-2-4
   1-4-3-2

The vast majority of inline or straight four-cylinder engines use this firing order because it has been credited with an overall smooth operation that produces few vibrations and more e​ven power delivery.

1. Highest redline ever
   Highest specific output for natural aspiration
2. Most torque output
   Biggest cylinder bores

When the S2000 launched in 1999, Honda used the little roadster to flex its technological muscles. The 2.0-liter DOHC-VTEC engine boasted a healthy 247 horsepower and 161 lb.-ft. of torque, which the automaker claimed was more power per liter than any other naturally-aspirated engine on the market at the time.

1. 2015 Camaro RT
   2016 Camaro ZR1
2. 2016 Camaro RS
   2017 Camaro T

GM caused waves when it introduced a Camaro powered by a 2.0-liter four-cylinder turbocharged motor. What's more, it was the same engine used in the Equinox, but has been well-received by many as being potent enough for the car.

1. Willys MB
   Ford Bronco
2. Land Rover Defender
   Jaguar Type-E

Most of the Jeeps used in World War II were powered by this famous engine, which was then used in a whole range of civilian Jeeps after the war was over. Willys-Overland produced this engine, which was equipped with a 1-barrel carb and was water-cooled.

1. 1984 Honda Civic
   1989 Acura Integra
2. 1990 Honda NSX
   1995 Honda Accord

After years of experimentation, Honda was ready to put variable valve timing technology, VTEC, in a production engine. The result was considerable surprise from the public and industry reviewers, because a compact and efficient car had a performance edge to it.

1. Series 1
   Series 2
2. Series 3
   Series 4

Thanks to issues Lotus has never clarified with the Rover K-Series engine, Lotus started using the Toyota 1ZZ-FE, a 1.8-liter engine. Other Toyota four-cylinder engines were used later, making for a successful partnership between the two companies.

1. Behind the driver and passenger
   Over the front axle
2. Over the rear axle
   In the front, behind the axle

With a mid-engine setup and carbon fiber monocoque, the Alfa Romeo 4C boasts a nearly perfect balance of weight between the front and rear portions of the car. That means excellent handling, making the 4C a true sports car.

1. Balance
   Cost
2. Weight distribution
   Consumers like them more

The inline four-cylinder engine has become incredibly common. They're relatively inexpensive to make, easy to install, and less costly to work on, making for a great option when people want an economical vehicle.

1. To boost acceleration
   To increase torque output
2. To reduce vibrations
   To anchor the engine securely

Four-cylinder engines aren't always the smoothest-running engine out there. To keep the car comfortable for drivers and passengers, automakers will use a balance shaft, which is a weighted shaft that counteracts vibrations.

1. They're too small
   They have little torque
2. The piston power strokes don't overlap
   They look funny

Thanks to the inherent design of inline four-cylinder engines, they can never have overlapping piston power strokes. Those gaps make the engine feel rougher and less refined, which is a big challenge in using four-cylinders for performance vehicles.

1. 2014 Mustang EcoBoost
   1993 Mustang SVT
2. 1974 Mustang II
   1967 Mustang

With the oil crisis in full swing, Ford decided to tweak the engine lineup for the Mustang II. That included using the same 2.3-liter four-cylinder engine that was in the Pinto, a move that angered many enthusiasts at the time.

1. 1-2-3-4
   4-2-1-3
2. 1-3-2-4
   1-4-3-2

Boxer engines not only have a different configuration, the firing order is also different from inline setups. In some ways, it reduces vibrations, but in other ways, it doesn't. One thing is for sure, this firing order results in a truly distinct sound.

1. They were hollow
   They were made of iridium
2. They are longer than the engine
   They have no lobes

Mitsubishi really went crazy on lightweighting for the Evolution, dropping weight wherever its engineers could think of practical ways. One was to use hollow camshafts. Another was to make the exhaust as straight and short as possible.

1. Twin-scroll turbo
   Roots supercharger
2. Centrifugal supercharger
   Turbocharging and supercharging

Normally, you wouldn't think a little 2.0-liter four-cylinder engine could get a big, heavy SUV like the XC90 moving in a hurry. Thanks to this unique setup, the supercharger provides great low-end power, while the turbo covers the top end of the spectrum.

1. F-150
   C-Max
2. Mustang
   Explorer

The 2.3-liter EcoBoost four-cylinder engine uses turbocharging, direct injection, and variable valve timing for a performance trifecta. The result is a peak 350 horsepower, which helps the car really move in a hurry.

1. Subaru and Nissan
   Subaru and Toyota
2. Subaru and Porsche
   Subaru and Volvo

While technically Toyota does sell the 86 coupe with a Boxer engine, that engine was developed by Subaru. Other automakers in the past produced Boxer engines, but for reasons such as increased complexity and production costs, they've all stopped.

1. Honda Civic Type R
   Detroit Diesel Series 50
2. 1996 BMW M3
   1996 Toyota Supra Turbo

Launched in 1993, this inline four-cylinder engine has a massive displacement of 8.5 liters. It's a smaller, four-cylinder version of the Series 60, using the same block, and is often found powering heavy trucks.

1. 1-3-4-2
   2-4-1-3
2. 1-2-3-4
   4-3-2-1

With few exceptions, V-4s use the same firing order as an inline four-cylinder, since it provides optimal balance for the design. Still, a V-4 doesn't have the same level of smoothness or balance you find in a V-6.

1. Honda Civic Type R
   Volkswagen Golf R
2. Mercedes-AMG GLA/CLA 45
   Subaru WRX STI

Mercedes and AMG found a way to extract 375 horsepower from a turbocharged 2.0-liter four-cylinder engine, something that ten years ago would have seemed completely insane. The move has kept it ahead of competing vehicles.

1. Highest rev limit
   Most power per liter
2. Largest displacement ever
   Full graphite construction

When the Acura Integra Type R launched in 1997, the car made waves in the auto industry. With 108 horsepower per liter, it set a record for the most power per liter for an engine. That helped smash perceptions that Honda's smaller cars were just grocery getters.

1. 2JZ
   LT5
2. QR25DE
   Small Block

Nestled under the hood of this performance compact sedan was a turbocharged 2.5-liter QR25DE four-cylinder. It was tuned for an impressive peak 200 horsepower, making the car entertaining for the driver.

1. 1.6 liters
   2.0 liters
2. 3.5 liters
   5.6 liters

The second generation of the MR2 was longer and heavier than the first, so it needed a more powerful engine. The 2.0-liter inline four-cylinder was positioned behind the driver and passenger for ideal balance, boasting a peak 156 horsepower and 137 lb.-ft. of torque.

1. With glow plugs
   With spark plugs
2. Through compression
   With magic

Instead of relying on a spark, diesel engines combust the fuel and air mixture by exerting extreme compression on it. This design has made diesels highly efficient, although modern gasoline designs are catching up.

1. Skyactiv-G
   Sky D
2. Turbosky
   Kompressors

The Skyactiv-G pushed Mazda's engineering further, combining a higher compression ratio, direct injection, heat-loss reduction, and premium fuel for improved efficiency that didn't sacrifice driving fun.

1. 3,000 miles
   8,000 miles
2. 12,0000 miles
   It depends on the engine

There is no one solution for all engines, since their designs vary so much. Automakers provide recommendations in the owner's manual, or you can call a local dealer to get that info, so you don't push the oil changes out too long.

1. Lower emissions
   Cheaper to make
2. Better fuel economy
   All of the above

You might have noticed that a steadily increasing number of cars, trucks, and SUVs use four-cylinder engines. Much of the shift has been driven by tightening fuel economy and emissions standards from governments, plus consumers wanting to save money.

1. The alternator
   The distributor cap
2. The battery
   The ignition wires

At very first, the spark plugs are powered by the car's battery. Once the engine is running, the alternator steps in, providing the juice the ignition system needs to keep things going, while also recharging the battery for the next startup.

1. 2JZ
   PR45
2. 1013E
   EA 189

The 2.0-liter turbocharged diesel engine was the pride and joy of Volkswagen, which proudly declared how cleanly the diesel ran, without sacrificing performance. Some cars using the EA 189 have returned to the road, after undergoing government-approved modifications to bring emissions levels into the legal limits.

1. 2.0-liter
   1.0-liter
2. 1.3-liter
   1.5-liter

Mitsubishi was well ahead of the curve when it created the Eclipse. Even the first generation of the car could be hard with a turbocharged 2.0-liter four-cylinder, which could send power to all four corners with all-wheel drive, a formula many automakers use today.

1. Turbocharging
   Variable valve timing
2. Nitrous oxide injection
   Supercharging

The variable valve timing tech in the Multiair is hydraulically actuated, which Fiat Chrysler says provides improved control of intake air. This innovation can boost horsepower by up to 10 percent and torque by up to 15 percent.

1. Honda
   Toyota
2. BMW
   Mitsubishi

This really shouldn't be a huge surprise, considering BMW owns Mini and the two automakers work together, sharing technologies and parts. Peak output from this engine is impressive at 228 horsepower.