Auto Classics International (ACI) was an American automotive manufacturer active from approximately 1994 to 1996, with operations based in Tempe, Arizona, and later in Hawaiian Gardens, California. The company specialized in producing replicas of classic racing cars, most notably the ACI Rennsport 550, which was modeled after the Porsche 550 Spyder. The ACI Rennsport 550 featured a round tube space-frame chassis and was powered by Volkswagen…