One of the rarest BMW M3s built in the model's illustrious 20-year history is going under the hammer at Shannons upcoming Melbourne auction on Monday June 5.

While 800 examples of the E30 BMW M3 Convertible were built between March 1988 and June 1991, only 137 of these were built with the most powerful 215HP incarnation of Paul Rosche's 16-valve 2.3 litre four-cylinder engine designed directly from BMW's Formula 1 experience.

Focusing even harder, just one of these 137 E30 M3 Convertibles is believed to have been painted Misano Red (colour code 236) - a colour normally reserved for the high-performance Evolution 2 and Ravaglia versions of the M3.

Add a very rare optional factory hardtop and the 1990 M3 Convertible being auctioned by Shannons on June 5 becomes a very desirable and collectable BMW at its anticipated selling price of $38,000-$44,000 (AUD).

Unveiled at the 1985 Frankfurt Motor Show, the M3 was a pocket-rocket built by BMW's Motorsport division to homologate the E30 3-Series for the European Touring Car Championship.

Using what was essentially the 24-valve head from the M-Sport straight six engine (minus two cylinders) mated to the block of the four-cylinder M10 engine whose origins dated from the company's successful 1.5 litre turbo F1 programme, the M3's motor developed an impressive 195bhp from 2.3-litres.



With a Getrag close-ratio five-speed gearbox, firmer suspension and additional downforce from the aerodynamic aids, the original M3 was one of the world's most dynamic performance cars.

However with a quoted top speed of 239km/h, the limited run of M3 Convertibles that were hand-assembled at the M-Division's Garching plant, became the world's fastest four-seater convertibles of their time.

More luxurious and generally better equipped than its closed M3 sibling, the Convertible featured a beautifully crafted leather interior with electrically operated hood (as found on the 325i Convertible) and combined the best of both worlds - race bred performance with the added versatility of refined open air motoring.

The vehicle being auction by Shannons was originally delivered to a German customer and spent some time in Holland before being professionally converted to right-hand drive by Birds, a UK factory authorised BMW dealership.

The car comes equipped with a full leather interior, electric windows, factory hardtop, Hartage 16-inch alloy wheels, an electrically operated hood and an Evo 2 spoiler. The engine has also been rebuilt to 215bhp Sport Evolution tune.

This extremely rare, hand-built piece of BMW Motorsport history is one of 46 vehicles and 17 memorabilia lots in the Shannons June 5 auction.

More info and pictures: http://www.shannons.com.au/marque/