It is rare for three manufacturers to introduce, on the surface, similar cars at about the same time. Rarer still for the three to originate in Germany.
Within the next three months, Porsche, BMW and Mercedes will announce new open-top cars, and although they do not directly compete with each other on price, comparisons will be made.
The Porsche Boxster has a 2.5 litre flat six engine, and BMW's Z3 Roadster is powered by a 1.9 litre, in-line four.
Top liner, though, is undoubtedly the Mercedes SLK, with its up-market 2.3 litre, supercharged four cylinder engine. And because it, like the Aston Martin DB7, uses a supercharger instead of a turbo, there is no throttle lag. Power is instantaneous.
Maximum power is an impressive 193bhp at 5,500rpm, while the all important torque figure is an equally impressive 206lb/ft, which Mercedes claims is almost constant between 2,500 and 4,800rpm, thanks to the Eaton supercharger.
For the uninitiated, a supercharger is engine-driven, usually by a belt, whereas a turbocharger is driven by exhaust gases. The SLK's 'blower' has a magnetic clutch, controlled by the computerised engine management system, which dictates when it should come in.
