The long career of the Porsche Turbo started during the first oil crisis--a time when it seemed that fast, powerful cars would have no further place on the motoring scene. Yet the Turbo has remained immune from such criticism ever since its debut at the Paris Motor Show in 1974. The evidence: a quarter of a century of unbroken success. In 1975, when the Turbo went into series production, 260 horsepower were sufficient to put across its power philosophy. The peak of the output curve was reached by the fourth generation of Porsche's top model in 1996, when the special Turbo S edition was rated at 450 horsepower. The most recent, fifth-generation Porsche Turbo endeavors to bring the fast driver that much closer to sports car perfection.