Unveiled at the 2010 Paris Motor Show, the Jaguar C-X75 could have been one of the British brand’s wildest and coolest models. It received the green light for production, got canned, and resurfaced in the 2015 James Bond movie Spectre before disappearing for good. However, not everyone has forgotten it: Callum, the design firm founded by former Jaguar design boss Ian Callum, has made a C-X75 street-legal.

Precisely how Callum’s customer ended up with a C-X75 remains a mystery. The example modified is one of the four surviving stunt cars built by Williams Advanced Engineering for Spectre, so it might be the one that auction house RM Sotheby’s offered at its Abu Dhabi sale in November 2019. The car was estimated to sell for anywhere between $800,000 and $1.2 million; it ended up not selling during the auction.

Regardless, Callum was the right person to take on the Herculean task of making an obscure, experimental supercar street-legal, as he led the team that designed the model. His company made hundreds of small but significant changes including replacing the glass, adding a quieter exhaust with catalytic converters, making tuning changes to the supercharged, 5.0-liter V8, and fitting additional switches inside. Interestingly, the stunt cars were built with foam door mirrors. These had to be replaced with real mirrors fitted with turn signal repeaters.

The team also took advantage of the tear-down to make visual improvements, such as reducing and aligning the panel gaps. The C-X75 received a new coat of paint, and engineers made changes to the suspension system — they notably adjusted the ride height. It helps that this version of the C-X75 uses an engine already approved for road use; the V8 has powered the Range Rover, among other cars.

Callum’s street-legal Jaguar C-X75 will make its public debut at the Bicester Heritage Scramble event held in England on April 21, 2024.

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