BMW 3 Series generations from the E21 to the G20: What is special about the BMW 3 Series?

"The essence of BMW is concentrated in the 3 Series," wrote Autorevue after its first encounter with the E46. The fourth generation of BMW's mid-size model is not unjustly considered by some fans to be the most harmonious 3 Series; its naturally aspirated inline six-cylinder engines are perhaps the best BMW has ever built.

But focusing on the six-cylinder engines would be unfair. Firstly, most 3 Series models left the factory with four-cylinder engines, and secondly, the company headquarters in Munich is not nicknamed the "four-cylinder" for nothing. Yet the inline six-cylinder engine runs like a thread through the success story of the mid-range model series of the brand with the white and blue propeller.

A success story began with its premiere at the IAA in the fall of 1975: The first BMW 3 Series, known internally as the E21, took over from the 02 series. Designed by Paul Bracq, it was only available as a two-door model – later joined by the rare Baur convertible, of which only 4,595 were built. In total, BMW built 1.364 million 3 Series E21 models.

Typical BMW features were already present: the double kidney grille, the Hofmeister kink, short overhangs, and, from 1977, the dual headlights. The rear end initially caused controversy, but BMW soon softened it with a black plastic cover.

BMW installs inline six-cylinder engines in the E21: the 320 and 323i make the 3 Series a sporty mid-size icon—the latter with 143 hp and a top speed of 190 km/h. The chassis, with spring struts and wishbones at the front and the semi-trailing arm rear axle, ensures excellent driving dynamics, and the rack-and-pinion steering ensures precision.

And inside? An innovation that continues to define BMW today: the cockpit angled toward the driver. The E21 thus laid the foundation for a lineup that made dynamic performance its trademark.

In 1982, the second generation of the 3 Series rolled out: the E30. For the first time, there was not only a two-door model, but also a four-door sedan, starting in 1983. The appearance was streamlined, and the drag coefficient was reduced by 15 percent. Dual headlights were now standard. The body was three centimeters shorter, yet offered more space inside. The track was 35 millimeters wider, and the weight was 30 kilograms lower—both of which helped with driving dynamics.

The engines produce between 90 and 171 hp. The base 316 model features a four-cylinder carburetor engine, while the 325i has a six-cylinder fuel-injected engine. The E30 is the first BMW to be available with all-wheel drive: the 325ix drives all four wheels via a transfer case and viscous locks.

The first 3 Series with a diesel engine was the 324d, featuring an 86 hp naturally aspirated inline six-cylinder engine. The turbodiesel in the 324td appeared in 1987 and produced 115 hp. With the 325eta, BMW introduced an inline six-cylinder gasoline engine with higher torque and lower revs in 1984. This fuel-efficient engine produced 122 hp and was the first 3 Series to feature a catalytic converter as standard.

But the real highlight is the sports version, unveiled at the same time: the first M3. Homologated model for the DTM, wider fenders, a high-revving four-cylinder engine, and later up to 238 hp. This definitively transformed the 3 Series into a motorsport icon.

In 1985, the Baur Topcabriolet faced serious competition from the factory: the convertible captivated with its elegant lines and easy-to-operate top. In 1987, the Touring expanded the 3 Series lineup with a practical version. Originally started as a DIY project by a BMW employee, BMW took over the design.

The E30 is the 3 Series generation in which BMW explores the diversity of variants – from family station wagon to racetrack star. The second generation surpasses its predecessor by almost one million vehicles, with 2.339 million units sold.

In 1990, the third generation of the BMW 3 Series was launched: the E36. Visually, it represented a major leap forward—lower, wider, more dynamic. The dual headlights were now hidden behind a glass cover, the roofline was dynamic, and the rear end ended with a spoiler lip. The coupe was no longer a simple two-door, but a distinct body style with few common parts to the sedan. From 1993 to 1995, BMW presented new body styles every year: the convertible, the 4.21-meter-long compact with a stubby rear end, and the station wagon known as the Touring.

The E36 is the most versatile 3 Series generation ever: sedan, coupe, convertible, touring, Baur top convertible—and the new Compact as a shortened hatchback version for the 1990s. Mechanically, it features a new rear axle from the BMW Z1 for enhanced driving dynamics. From 1992 onward, all 3 Series models feature ABS as standard. ASC traction control is available as an option, available from 1997 as ASC-T with stabilizing brake intervention.

Engine-wise, the range extends from the four-cylinder 316i to the 328i with its powerful inline six-cylinder. And of course: the M3. First as a coupe, later also as a sedan and convertible. The look is significantly simpler and closer to its civilian counterparts. Initially as a 3-liter with 286 hp – from October 1995 with a 3.2-liter, 321 hp, and for the first time with a 6-speed transmission and Double Vanos. Starting in 1996, the M3 was offered for the first time with the option of the sequential manual transmission (SMG for short), which was unfortunately very fragile in the initial version.

With over 2.7 million units built, the E36 made the 3 Series more aerodynamic, sportier, and more versatile—and shaped the 1990s like baggy pants and modems. BMW sold 2.745 million units of the third-generation 3 Series.

In 1998, BMW unveiled the fourth generation of the BMW 3 Series with the E46. Sedan, Coupé, Convertible, Touring, Compact, and M3 – for the first time, the model lines exhibited clear design differences. The signature BMW kidney grille was integrated into the hood. Length and width each increased by four centimeters, giving the sedan a more robust stance and providing a bit more space for passengers. Yet a 3 Series still fits like a slim-fit suit.

As with its predecessor, there's a compact, a coupe, a touring, and a convertible. The open-top version features a heated glass rear window, seatbelts integrated into the front seats, and two roll bars that pop up behind the rear headrests in the event of an emergency. A practical detail: the touring gets a separately opening rear window.

Technically, the E46 boasts proven four- and six-cylinder inline engines, along with innovations such as direct-injection diesel engines, aluminum chassis, and SMG for the two six-cylinder 325i and 330i models. The new six-cylinder inline diesel in the 330d features common-rail injection and produces 184 hp from a displacement of three liters. The 320d, with its 136 hp four-cylinder turbodiesel, becomes one of the best-sellers in the engine range—for the first time, both a coupe and a convertible are available with diesel engines.

The M3 impresses as a coupe and convertible with 343 hp, wider wheel arches, a power dome on the hood, and a variable M differential lock. A lightweight special model of the M3 CSL is available with 360 hp, a carbon roof, and an optimized chassis.

With 3.267 million units sold, the E46 is the best-selling 3 Series generation – a classic that some consider the most harmonious 3 Series.

With the fifth generation, introduced in 2005, the E90, not only saw a major leap in the model line designation. The team led by chief designer Chris Bangle also gave the 3 Series a significant makeover: it became more modern, with distinct lines for the sedan, coupe, convertible, and touring. For the first time, it lacked a driver-focused cockpit, but instead featured iDrive – a first in the midsize class. The convertible received a steel folding roof, and the coupe a completely unique body.

New features under the hood: The 320i is now a four-cylinder, and the 335i is the first turbocharged gasoline engine in the 3 Series. The twin-turbo inline six-cylinder produces 306 hp. The three-liter diesel engine in the 335d, with two turbochargers, produces 286 hp. The inline six-cylinder gasoline engines in the 325i and 330i feature particularly lightweight magnesium-aluminum crankcases. The dual-clutch transmission also makes its debut, enabling lightning-fast gearshifts.

And of course: the M3. Now with a 4.0-liter V8, 420 hp, high-revving technology, and top speeds of up to 280 km/h – a true technological statement surpassed only by the strictly limited extreme versions, the M3 GTS and CRT.

With its blend of high-tech, new operating concepts, and driving pleasure, the E90 defined the 2000s – just like YouTube, smartphones, and Harry Potter. BMW sold 3.102 million units of the fifth generation.

In 2011, the sixth generation of the BMW 3 Series was launched: the F30. Its design was more dynamic, with slimmer headlights that, for the first time, were positioned directly next to the kidney grille. The design was inspired by the 5 Series, but had a distinctive and sporty feel.

The sedan is 9 centimeters longer than the previous model. The wheelbase has grown by 5 centimeters, and the track width has increased by 3.7 centimeters at the front and 4.7 centimeters at the rear.

The series is becoming more versatile: sedan, touring, and—new—the Gran Turismo, which offers more space with its coupé roofline and long wheelbase. The coupé and convertible, however, are moving into their own family: the BMW 4 Series.

An era is coming to an end on the engine side: naturally aspirated engines are history, and all engines now rely on turbocharging. Starting in 2012, the ActiveHybrid 3 will be available for the first time as an electric-assisted model. A unique feature: starting in 2015, the 318i will be powered by a three-cylinder engine.

Completely different: the M3. Now only available as a sedan, with a 3.0-liter twin-turbo inline six-cylinder, producing at least 431 hp and significantly lighter than its predecessor.

The F30 brings the 3 Series into the modern age. And visually, some already consider it a classic of the future.

BMW unveiled the current G20 generation in 2018. Visually more modern, with sleek lights, a distinctive kidney grille, and a clear focus on digitalization. Length, width, and wheelbase grew by 7.6, 1.6, and 4.1 centimeters, respectively.

The 3 Series remains available as a sedan and touring body style. The coupe and convertible remain called the 4 Series. New, however, are more assistance systems and even greater connectivity. The cockpit consists of a 12.3-inch screen for the instruments and a Control Display. Users operate the 3 Series using touch functions, the iDrive Controller, steering wheel buttons, and gesture or voice control.

Four-cylinder engines dominate, with only the top models still featuring inline six-cylinder engines. And the manual transmission is almost completely gone – only the base M3 still has three pedals. Plug-in hybrids expand the lineup, and the electric 3 Series i3 is also available in China.

And the M3? For the first time, it's also available as a Touring version, with up to 550 hp in the M3 CS. It still features a twin-turbo inline six-cylinder, optional all-wheel drive, and plenty of motorsport flair – even for everyday family use. The G20 brings the 3 Series into the digital age – with more technology, more variety, and an M3 version that offers everything without compromise.