Oldsmobile F-88 Mark III, 1959. Designed by Harley Earl, the third is a series of F-88 concepts had a body made from fibreglass and steel with a retractable brushed aluminium hardtop. It was powered by an experimental 250hp fuel injected 324ci ‘Rocket’ V8. However General Motors were concerned about the creation of an in-house competitor for the Corvette so the F-88 didn’t progress beyond the prototype stage. Harley Earl used the F-88 Mark III in his retirement but the fate of the car remains unknown