 A small amount of the final twin turbo cars and the Speedsters (10 Series 1 Speedsters w/ L98 Twin Turbo) were designated 500 Series Callaway Twin Turbo Corvettes.These unique cars came with OZ Racing wheels and Bridgestone Potenza tires, a "500 Series" dash plaque, "500 Series" intercooler badge, special car bra, car cover and floor mats.Regarding the "production" of the Callaway Sledgehammer, Reeves Callaway used a production Callaway Twin Turbo Corvette, 1988–051, to be precise.