Recently BMW Technik celebrated its 25th anniversary by rolling out a few rarely seen concepts and one that has (up until now) only been rumored, the Z29. The two door coupe is the very concept that several publications reported on around the 2000 time-frame. At the time there was talk of a small two door concept with liberal use of carbon fiber and innovative use of reinforced plastics deep within the confines of BMW ‘s Munich HQ. That was this car and this is it ‘s story.

The Z29 never reached production but that doesn ‘t mean it ‘s not one of the most important BMW ‘s of the past 15 years. The ideas, engineering and design technics have informed many BMW product since (and some we haven ‘t seen yet).

The key stat of the Z29 was clearly the weight. At 2560 pounds the Z29 had a staggering power to weight ratio of 7.46 hp/lbs. That of course is thanks to the S54 E46 M3 inline six under the hood producing 343 hp. That ratio is not only dramatically more than any other BMW currently in production but on the level of some supercars.

The Z29 would hit sixty in 4.4 seconds from a full stop and continue all the way to a 168 mph top speed. Power was fed through the E46 M3 ‘s six speed SMG.

And the looks? Yes the Z29 isn ‘t the most innovative design. But that ‘s not the point of the car or Technik as a think tank. The idea is simply to push the limits of technology and engineering to better inform future BMW products. The Z29 stunning on those terms. Light, agile and everything you ‘d want in a focused two seat sport coupe.

The following is BMW Technik ‘s official press release detailing the secretive project.

>Optimization of the vehicle weight by deploying the most advanced high-tech materials was the focus of development for the BMW Z29 concept study. The prototype of a two-seater sports car was completed by BMW Technik GmbH in 2001 and represents the culmination of cooperation with another subsidiary of the BMW Group – BMW M GmbH. The vehicle exerts fascinating appeal with flowing lines and lambo-style doors. The principles underlying the outstanding potential of the BMW Z29 for dynamic driving can be found under the engine bonnet and below the surface of the paintwork. The power was generated by the in-line six-cylinder engine of the BMW M3 – at that time a technological benchmark – and the passenger cell was manufactured from carbon-fibre reinforced plastic while the rear axle, and front and rear module were designed in aluminium. The most important results of this combination: a weight-to-power ratio of 3.4 kg/hp and anBMW Group acceleration ratio of 4.4 seconds for the sprint from a standing start to 100 km/h.

>Consistent lightweight construction formed the focus of BMW Forschung und Technik GmbH and BMW M GmbH in the BMW Z29 project that was brought to fruition in 2001. The engineers created an emotional, thoroughbred sports coupé as a concept vehicle powered by the in-line six- cylinder BMW M3 engine, which at the time generated 252 kW/343 hp. However, the lambo-style doors clearly marked out the visual appearance of the concept car from all the series models manufactured under the brand.

>The BMW Z29 accommodates a maximum number of two occupants in the passenger cell with a structure comprising a monocoque made of carbon- fibre reinforced plastic. A front module manufactured in aluminium is bolted onto the monocoque to accommodate the six-cylinder power unit mounted as a front mid-engine and the double wishbone front axle also made of aluminium. A sequential M six-speed gearbox transfers power to the rear axle. Aluminium for the rear module and rear axle also plays a role in reducing the weight of the vehicle still further.

>The engineers garnered further weight savings with innovative structures in the cockpit. The air outlets from the ventilation system were designed as a structural member on which the instrument panel is mounted. This measure and similar design features reduced the kerb weight of the vehicle by some 26 kilograms.

>The prototype has a length of precisely 4 metres and a height of 1 265 millimetres. The weight of the vehicle ready to roll is only 1 160 kilograms. The resulting weight-to-power ratio is 3.4 kg/hp and is at the level of a thoroughbred racing car. The axle load distribution achieves the ideal value of 50:50. The performance and handling are equally impressive. The BMW Z29 sprints from a standing start to a speed of 100 km/h in just 4.4 seconds and boasts an impressive top speed of 270 km/h.