The BMW 3 Series is a compact executive car manufactured by the German automaker BMW since May 1975. Successor to the BMW New Class, it has been produced in six different generations and in five different body styles. It is BMW's best-selling model, accounting for around 30% of the BMW brand's annual total sales (excluding motorbikes).[1] The BMW 3 Series has won numerous awards throughout its history.

BMW released its E21 in the wake of the 1973 oil crisis, nearly doubling BMW's worldwide auto sales figures in three years. The 3 series has also maintained BMW's racing heritage. The M version of the 3 series, M3, debuted in 1988.[2]

There have been six generations; their respective chassis codes are:

The first generation was a two-door saloon model only. A factory authorised cabrio version was also built by Baur.

The cockpit design of the E21 marked the introduction of a new design concept for BMW, with the center console angled towards the driver. This feature has become part of BMW’s interior design philosophy for many years. As a sign of passive safety, all edges and control elements within the interior were rounded off and padded.

Initially, all models used the BMW M10 four-cylinder engine. In 1977, the BMW M20 six-cylinder engine was added to the lineup.

The E30 was sold from 1982 through 1991 in saloon form, and through 1993 in convertible form. Four-cylinder and six-cylinder petrol engines were used, with a six-cylinder diesel added in 1985. In 1987, the first all-wheel drive 3-series was produced, called the 325iX. The E30's introductory price was nearly double that of the E21 just seven years earlier[citation needed].

Initially released as a two-door coupe, the four-door saloon body style was added to the 3-series lineup in 1984. In 1987, the station wagon ("touring") body style became available.

The first BMW M3 was the E30 M3 coupe, which was released in 1987 and uses the S14 four-cylinder engine.

The E36 was produced from 1990 - 2000. It was available with four-cylinder and six-cylinder engines, with the twin cam BMW M50 six-cylinder replacing the single-cam engine used in the E30. Rear suspension was the "Z-axle" multilink suspension, as used in the Z1.

Initial sales were the four-door sedan, with the coupe version added in 1991 and the cabriolet version in 1992. Finally, the station wagon ("touring") version was produced from 1994.

In 1992, VANOS variable valve timing was introduced on the DOHC I6 (inline 6-cylinder) engines. In 1996, the M50 six-cylinder engine was replaced by the M52 six cylinder engine, and maximum displacement was increased from 2.5 litres to 2.8 litres.

The E36 M3 uses the S50 (or S52 in North America) six-cylinder engine and was the first M3 available as a four-door sedan.

The E46 was introduced in 1998 as a 1999 model, in saloon version only. In 1999, the station wagon ("touring") and coupé models were added. The convertible and M3 were released in 2000. The E36 was available with four-cylinder and six-cylinder engines. All-wheel drive was introduced as an option in 2001 (for left hand drive markets only).

In 2000, the M54 six-cylinder engine replaced the M52 and maximum displacement increased from 2.8 litres to 3.0 litres.

Also in 2000, the E46 M3 Coupe coupe was released. It uses the S54 six-cylinder engine and the option of an automated clutch SMG gearbox. In 2002, the convertible M3 became available.

The highest selling year for the E46 was 2002, when 561,249 vehicles were sold worldwide.[3] For every year of its production, the E46 was named in Car and Driver Magazine's "10 Best Cars" list (see Car and Driver Ten Best).

The E90 debuted as a saloon (E90) and touring (E91) in March 2005, while the coupé (E92) and a retractable hard-top convertible (E93) went on sale in August 2006.[citation needed] The coupé/cabriolet body was now its own design and no longer derived from the saloon/touring (unlike its predecessors).[citation needed] The retractable hard-top convertible, meanwhile, was a first for the 3 Series.

The E90 was available with four-cylinder and six-cylinder engines, and the E92 M3 used a V8 engine. The first turbocharged petrol 3-series was the E92 335i, which uses the BMW N54 straight-six. The N52 naturally aspirated inline-six engine features a lightweight magnesium/aluminum construction, electric water pump, and Valvetronic variable valve lift.

In 2007, a record total of more than 550,000 vehicles were sold and it was the seventh most popular car in the United Kingdom.[4]

The sixth and current generation of the BMW 3 Series debuted on October 14, 2011 in Munich. The model arrived in showrooms in February 2012. Many of the six-cylinder petrol models of previous generations (eg 328i) are instead powered by turbocharged four-cylinder engines for the F30.

The first model of the F30 to debut was the sedan/saloon, which will be followed by the wagon, gran turismo (GT) high-roof five-door,[5] coupé, and hardtop convertible body styles afterward.

The F30 lineup will not include convertible, coupé, and gran coupé models, as these will be badged as BMW 4 Series models.[6]

There will also be a hybrid version which augments the transmission with two electric motors and expected fuel savings of 20 percent, a similar powertrain that will be found in the upcoming X5 hybrid, developed in a joint venture with GM, Chrysler, and Daimler. [7]

The 3 Series has been on Car and Driver magazine's annual Ten Best list 22 times, from 1992 through 2012, making it the longest running entry in the list.[8] In their December 2009 issue, Grassroots Motorsports magazine named the BMW 3 Series as the second-most important performance car built during the previous 25 years.

The E90 was named "Best New Sports Sedan" in the 2006 Canadian Car of the Year awards. Also, it was awarded the World Car of the Year at the New York Auto Show in 2006. What Car? also awarded the E90 2006 "Car of the Year". The E90 was also awarded Japan's Import Car of the Year for 2005/06. BMW emerged as the brand winner at the International Engine of the Year Awards for 2007 with its award in the 2.5- to 3.0-litre segment won by the 3.0-litre twin turbo engine, which is found in the BMW 335i.[9] The BMW 320d EfficientDynamics Edition was nominated as finalist of the 2011 World Green Car of the Year, and the winner will be announced at the 2011 New York Auto Show.[10]

The 3 series won the Best Executive Saloon from the Scottish Car of the Year 2012 held at Glasgow on the 14th October 2012.

The 320d Touring was named "The Family Car of the Year 2012" by Top Gear (magazine).

The E36 320d won the 24 Hours Nürburgring in 1998, after the M3 had won in the previous years.

The World Touring Car Championship (WTCC) is one of the FIA's three World Championships (along with Formula One and the World Rally Championship). Andy Priaulx and BMW Team UK won the ETCC in 2004, and continued the winning form in WTCC in 2005 in an E46 3 Series, while the E90 3 Series repeated this feat in 2006 and 2007.

The 3-Series cars in the British Touring Car Championship (BTCC) and other touring car championships have been penalized under racing rules for being rear-wheel drive and thus having better grip than its front-wheel drive competitors. For example, the 320si has been penalized in the WTCC in previous seasons in order to keep the sport competitive with the rest of the grid (Ford Focus, Chevrolet Lacetti, SEAT Leon, Alfa Romeo 156). Despite these ballast weight penalties, the 320si's of the British, German and Italian/Spanish teams continually win races and points.[citation needed] However, in the middle of the 2002 European Touring Car Championship (ETCC) season, FIA changed the handicap rules to add an extra 15 kg (33 lb) ballast to front-wheel drive cars (such as the Alfa Romeo 156) and the ballast in rear-wheel drive cars (including BMW) was reduced by 15 kilograms (33 lb).[11] Today, the WTCC series has a rolling start to eliminate the benefit of better grip that rear-wheel drive cars have from a standing start.[citation needed]

The BMW 3-Series is currently used in both the SCCA Pro Racing Speed World Challenge Touring Car Series and the Grand American Road Racing Association Series. In the final 2006 Grand Am standings, BMW finished second in the manufacturer's standings in both the Grand Sport and Street Tuner classes, while E46 BMWs prepared by Turner Motorsport won the driver's and team championships.[citation needed]