With the spectacular success of the New Class and the 02 Series, BMW had come off the ropes to reach new heights of prosperity. In the early seventies, a new plant was set up in Dingolfing to help spur sales. BMW wanted to produce 1000 cars a day. In 1972, it introduced the replacement to the 1800/2000. This new offering was a traditional mid-size model designed by Marcello Gandini and reintroduced the now-familiar nomenclature. It was called the 520 (E12).
BMW chairman Eberhard von Kuenheim described the company ‘s product plans through the 1980s as a program of “refinement in all areas.” He had expressed his concern over not being able to economically produce cars smaller than the 1502. The 5 Series was the first step towards the intended market. It featured a refined body design and great interior comfort. Due to its extra weight over the New Class sedans, it however was not a particularly brilliant performer.
The twin-carb base model could sprint to 60 mph in about 12 seconds and run to its top speed of 108 mph propelled by its 2.0 liter 115 hp four-cylinder M17 engine. The fuel injected 520i could do 60 mph in about 11 seconds while on its way to a 114 mph top speed. Many may wonder what the “i ” stands for in modern BMW naming- it signifies the car is fuel injected and is a throwback to this period in BMW ‘s history when cars with carbs were offered alongside those with fuel injection. A few years later the 5 Series was first imported to the US by Max Hoffman (just before he sold his stake to what is now BMW North America). It was a federalized car, modified profusely for the wallow of government safety and emissions regulations taking place at the time.
Later in the cycle a 530i was introduced with a detuned version of the 3.0 liter six cylinder engine found in the CS/CSi coupes. With an 8.1:1 compression ratio and featuring Bosch L-Jetronic fuel injection, power output was 176 bhp at 5500 rpm with peak torque of 185 lbs/ft developed at 4500 rpm. With mostly minor year-to-year changes, and a facelift in 1977 raised the twin-kidney grille and featured a revised hood, plus redesigned taillights and fuel filler. The original E12 5 Series continued through to 1981. The E12 M535i is the only official BMW Motorsport-developed version of the E12 5 Series. It is the only E12 model powered by the 3.5-liter M30 inline-six from the E23 735i and E24 635CSi. It featured a BMW Motorsport-tuned chassis and several unique cosmetic items. This was a limited run car and was never officially released in the US market, while not a full on ///M this car was the starting point of many things to come from BMW and the Motorsport division.
After eight years of production, the E12 5 Series was certainly due for an update. BMW had been working on a successor since early 1975 and it was time to unveil it. The E28 was a second-generation design which left the factory in June 1981. It was virtually an all-new car. The central body structure was the only carryover from the old model. It was substantially changed in the areas of engine, suspension, ventilation, weight distribution, transmission, steering and brakes.
The styling and body engineering was changed, providing better streamlining and enhanced motoring comfort. The one major issues was that Claus Luthe ‘s new redesign was so subtle that the new 5 Series was hardly distinguishable from the old one. It was greeted with disbelief. Road & Track commented; “We ‘ve argued for years against change for the sake of change, but there ‘s a limit and BMW is probing it…” Being a stylistic evolution of the E12, the shape was more rounded than boxed at the rear, a very subtle change.
Other than revised headlights, thicker bumpers and large rectangular taillights, visible differences were scant. Despite this, the 5 Series sold well, accounting for about 30 per cent of total BMW sales at the end of its production run. It was available in Europe with a choice of four different powerplants. Of course, none of these variants ever saw the US shores. A special economy model was shipped, called the 528e, created expressly for the US government ‘s rising corporate average fuel economy targets. The 528e utilized the “eta ” motor, low revvingwith high torque, much like a diesel to improve overall operating efficiency. A new automatic transmission was also offered as an option because of America ‘s growing preference for the luxury of not having to shift one ‘s own gears.
The launch in 1984 of a particular kind of 5 Series marked a defining moment in BMW history. Unlike all other 5 Series, this was developed exclusively with high performance in mind. Hand made by BMW ‘s Motorsport division on a 535i chassis, it featured a modified M1 24-valve dual overhead camshaft inline-6 engine with six individual throttle bodies and Bosch Motronic integrated fuel injection. At the time of its introduction in Amsterdam, it was the fastest production sedan in the world. This was the first ///M5.
With under 2,200 examples produced, it remains one of the rarest M cars BMW has ever made. If there was ever a question of BMW ‘s ability to produce fine sports sedans, the /// M5 was quite an answer. It fulfilled the demand of a sedan ‘s practicality and a sports car ‘s performance in a single package, something the world had not experienced before. The European spec M88 engines produced 282 bhp, while the American spec S38 engines produced 256 bhp, on account of having lower compression and different timing chains.
The future of all BMW ///M cars would be greatly influenced by this foray into exciting, elegant performance. Being the spiritual and direct successors to the New Class, the introduction of the BMW 5 Series was crucial from a marketing stand-point and to the success of the company. The New Class was getting old, and with lessons learned from its own history, BMW paved the road for a future where BMW would be recognized as the very essence of sport combined with engineering originality, brilliant execution and quality.
Since the original introduction of the 5 Series in 1972 there have been five versions of the model. The original two we have discussed here, as well as the E34 ( ’87- ’94), E39 ( ’95- ’02), and the E60 ( ’03- ’10). The newest model, coded F10, will hit the US shores this June and will be a car that embraces new technologies for efficiency and driving pleasure but would not be half the car it is without its ‘ history.