The famous actor and founder of the Sundance Film Festival also had great taste in cars, as exemplified by this rare Porsche 904 GTS Coupe. The 904 GTS was built over the course of only two years, between 1964 and 1965. The car’s engine made it a “giant killer”, going after race cars with more displacement, power, and a few more cylinders. The flat-four was mid-mounted like the layout of the record-setting Porsche 917. The 904 GTS’s motor, mated to a five-speed manual transmission, was good for 180 horsepower and was dubbed, “probably the most complex four-cylinder” ever made. This specific car spent a fair amount of time at the racetrack prior to its purchase by Redford, who owned it for the better part of a decade. It has been restored, and a period-correct engine from a Porsche 911 was swapped in, the same mill used in late model 904s. Only 110 of them were made, so it is indeed a car to covet thanks to its history and its famous owner. It’s up for auction via Bonhams and just might clear upwards of $1.7 million.