When a brand has a history as long and as proud as Porsche, there are bound to be plenty of iconic models. While the Porsche 911 has been the brand’s signature model for decades and the basis for many special models, including competition models, the 1964 Porsche 904 was just as capable in its own segment. In 2020, Porsche revealed a series of previously unrevealed concepts that show that the 904 almost got a spiritual successor back in 2013. It was called the Porsche 904 Living Legend (LL), and here’s what it would have been had Porsche decided to make it.

While we don’t know why Porsche did not go through with the 904’s modern successor, we know that it would have been an ultra-light mid-engine sports car. How light, you ask? Porsche never revealed exact figures, but there is a car that exists that can give us plenty of clues – the Volkswagen XL-1.

While the XL-1 came with a hybrid powertrain, consisting of a 0.8-liter TDI twin-cylinder engine and an electric motor, that produced 68 horsepower and 103 pound-feet (140 Nm) combined, it spawned an even crazier vehicle, called the Volkswagen XL Sport.

While both models entered limited production, it was the XL Sport that served as the basis for the Porsche 904 LL. It’s no surprise then that the mid-engine Porsche concept was powered by the same Ducati 1.2-liter V-twin engine, which developed 200 horsepower at 12,000 RPM. In terms of the weight, the XL Sport and by extension the Porsche 904 LL, had a curb weight of 1,753 pounds (795 kg).

The Ducati V-twin engine was mated to a seven-speed DSG (dual-clutch automatic), which allowed the mid-engine car to sprint from 0 to 60 mph (97 km/h) in 5.7 seconds, and on to a top speed of 168 mph (270 km/h). With a curb weight like this and a motorcycle engine positioned in the middle, the Porsche 904 Living Legend would have been the ideal track car.

While the 904 LL could have been a great homologation special for a GT4 race car, Porsche never planned on making a production version of it, instead opting to continue the development of its other mid-engine model, the Boxster/Cayman. The closest thing to it remains the 2015 Volkswagen XL Sport, which was produced in only 250 copies.