This 1993 CVT F1 Car Was Banned Before It Could Compete

If word got out that Williams Racing was secretly a NASA subsidiary in the early 1990s, Formula 1 fans wouldn’t be too shocked. In an era when regulations were still relatively open in the sport, Williams was on the absolute cutting edge, with the Oxfordshire, England-based team utilizing active suspension, automatic gearboxes, power steering traction control, antilock brakes, and enough data and telemetry sensors to make a satellite jealous.

The mad science reached its boiling point in 1993, when the team experimented further with gearbox technology, developing a continuously variable transmission (CVT) for that season’s contesting FW15C. In modern days, any enthusiast associates CVTs and their assorted pros and cons with econoboxes like the Toyota Prius or Nissan Sentra. However, in one of the strangest-sounding tests of all time, Williams proved that the single-speed gearbox could prove to be the ultimate advantage for the team … so much so that the car wouldn’t make it past a single on-track test before the ruling Fédération Internationale de l’Automobile (FIA) forbade it.

Unlike a more conventional transmission, a CVT doesn’t have multiple gears; rather, it has two cones or pulleys, with one connected to the engine and another connected to the wheels. These pulleys can change their diameter, which allows the gear ratio to change on the fly. Increase the size of the drive pulley and decrease the diameter of the driven pulley, and the gear ratio gets larger, giving more speed. Make the drive pulley smaller and the driven pulley larger, and you’ve got a shorter gear ratio, with more power and torque on tap. For visual reference, someone’s made a great example out of Legos to help explain how the transmission works.

This lets the engine essentially run at a fixed rpm, regardless of speed. It’s perfect for economy cars, giving them smooth acceleration and far better fuel efficiency, but Williams knew the gearbox was also the perfect choice for constant power.

The FW15C was equipped with a Renault V10 that could make 780 horsepower, but only when the tachometer reached 13,800 rpm. The beauty of the CVT is that it could keep the car constantly in that maximum powerband. Whether launching out of a corner or at the end of a long straightaway, it was making maximum power all of the time. With no lost time or focus shifting gears, FW15C had the potential to be an absolute beast in straight-line speed.

On a rainy day in July of 1993, Williams test driver David Coulthard would put this tech to the test at Pembrey Circuit in Wales. Coulthard’s teammate Alain Prost jokingly described the car as “a little Airbus,” per Sports Car Market, because of how much modern tech was shoehorned into the car. And when Coulthard hit the track, it sounded the part, too.

An F1 car going around at full song with its engine revs sitting north of 10,000 rpm makes for easily one of the strangest sounds in motorsports. But this one worked, with its gearbox allegedly dropping seconds off its pace around the test track compared to the conventional Williams’ transmission … in a car that was already wiping the grid at the time.

The FIA wanted teams that weren’t Williams to win in the coming years, and as a result, stepped in to regulate. As part of a major rules package for the 1994 season, the FIA mandated that all cars had to have four to seven fixed gears. And to make things even more emphatic, it threw in a sub-clause banning the CVT. As a result, the CVT never actually found its way to on-track competition in the Formula 1. But the FW15C gave us a taste of what the pinnacle of motorsports might have looked and sounded like.