Koenigsegg isn't normally associated with motorsports, but it did build one race car, and it's slated to be auctioned off by Bonhams at the 2023 Goodwood Festival of Speed on July 14.

First spotted by Robb Report, the 2007 Koenigsegg CCGT GT1 Competition Coupe was based on the CCX supercar and designed for the GT1 class of sports-car racing, which at the time featured cars such as the Aston Martin DB9 and Chevrolet Corvette C6.

2007 Koenigsegg CCGT GT1 Competition Coupe (photo via Bonhams)

2007 Koenigsegg CCGT GT1 Competition Coupe (photo via Bonhams)

We never got the chance to see how the CCGT GT1 compared to its more established rivals, however. Before the Koenigsegg race car could turn a wheel in competition, the GT1 rules were changed.

The car up for auction is the single proof-of-concept version built by Koenigsegg, according to Robb Report. In keeping with GT1 rules, the bodywork doesn't deviate too far from the CCX road car, the main exception being a large rear wing.

2007 Koenigsegg CCGT GT1 Competition Coupe (photo via Bonhams)

2007 Koenigsegg CCGT GT1 Competition Coupe (photo via Bonhams)

A 5.0-liter V-8 produces 600 hp, which is actually less than the road car due to racing rules. Other highlights include a double-wishbone suspension, gas-hydraulic shocks, and carbon-ceramic brakes with 6-piston monobloc calipers. The 16-year-old car has also been certified by Masters Historic Racing for the Endurance Legends Series, so it can finally be used as intended.

After Koenigsegg canceled the racing program, the CCGT GT1 went to shareholder Bård Eker, according to the auction listing. The listing also states that Eker maintained the car, kept it in a temperature-controlled dark, dry storage area, and brought it out for twice-yearly exercise runs. Bonhams expects the race car to sell for between $3.8 million and $5 million when it crosses the auction block.