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The Duntov Turbo was built as a partnership between American Custom Industries (ACI), a company known for building replacement Corvette body panels, and Zora Arkus-Duntov. It was developed as a highly-stylized convertible sports car based on the production model Corvette. Each of the special Duntov Turbo's also came with a turbocharged V8.
Chevrolet's introduction of the LT1 in 1992 as the base engine in the Corvette phased out the L98 based Callaway Twin Turbo. Previously, Callaway Corvettes made their increased power through positive manifold pressure; now they made it through increased displacement and finesse. Initially called the CL1 or CR1, they designated the chassis they were built upon. They were based on the pushrod LT1 cars (CL1) or the 32 valve DOHC LT5 ZR-1 cars (CR1).
In 1989 Callaway introduced a Speedster which was the culmination of their styling, engineering and trimming talents. Their first example was a bright green ZR1, which had a severely chopped windscreen, no side mirrors, eighteen inch wheels and a vibrant blue leather interior stitched purposefully from Germany. Nothing about Callaway’s Speedster was reserved, and this is especially true when investigating the specification. The car had 450 horsepower.
The Zagato company took a C7 Corvette Z06 and transformed it into the IsoRivolta GTZ, a "spiritual descendant" of the Iso Grifo A3/C (Corsa).  The original A3/C race car was developed by Giotto Bizzarrini not long after he left Ferrari, where he had served as cheif engineer behind the 250 GTO, which is revered as the world's most expensive car.  Bizzarrini purportedly fancied the A3/C as his "own personal evolution of (and improvement upon) the GTO design."