The definitive account of the evolution of the Porsche 944. What began as showroom-stock racing in the late 1970s evolved by the spring of 1985 into a global phenomenon: a single-marque racing series known as Porsche Cup, using a bespoke, factory-built race car. This book documents the development of that car--the 944--which was initially dismissed by some as a "Volkswagen with a Porsche badge" but soon proved itself a serial race winner. Porsche Cup began as a humble grassroots effort to boost sales of an entry-level vehicle, yet it ultimately changed the landscape of motorsport forever. The Rothmans Porsche Turbo Cup explores the evolution of the front-engine Porsche concept, the races that forged its reputation, and the formal factory-supported series established around the 944. Extensive archival research reveals the inner workings of the Cup, while interviews with the series' architects and drivers paint a vibrant picture of the era. Illustrated with previously unpublished images that capture both the facts and the ambiance of the time, this volume brings a history that has lain dormant for over thirty years back to life.