Having established the Chaparral 2 as a competitive force in American sports car racing and Can-Am competition, Hall and Sharp turned their attention to the FIA World Sportscar Championship for 1966. Endurance racing in Europe required a different approach to the open American circuits: longer races, a wider variety of track types, and FIA regulations that mandated closed-cockpit bodywork for Group 6 prototype entries. The 2D was developed specifically to meet these requirements, adapting the existing Chaparral mechanical package into a closed coupe body.
The 2D was powered by a 327-cubic-inch aluminium alloy Chevrolet engine displacing 5.36 litres and producing 420 horsepower. In closed-cockpit trim the car weighed only 924 kg, making it relatively light for an endurance prototype of the era. The closed body also incorporated the air intake periscope on the roof that was a signature visual feature of the car — a design element that appeared on other contemporary machines including the Fiat Abarth OT 1300 and was later adopted in Formula One. The 2D used Chaparral's established semi-automatic transmission, which kept the driver's left foot free and gave the car a mechanical character quite different from European rivals using conventional gearboxes.
The 2D did not carry the high-mounted rear wing that would appear on its successors. The aerodynamic emphasis was primarily on managing airflow over the closed body rather than generating large amounts of downforce through external wing structures.
The 2D made its World Sportscar Championship debut in 1966 with Phil Hill as the lead driver, supported at various rounds by Jo Bonnier and Hap Sharp. The car's best result came at the 1966 1000 km Nürburgring, where Hill and Bonnier drove to an outright victory against a strong international field. The result demonstrated that Chaparral's technical approach could be effective against the leading European marques on their home circuits. The 2D also competed at the 1966 24 Hours of Le Mans, running competitively before withdrawing after 111 laps with mechanical problems.
The 1967 season saw the 2D give way to the 2F, which applied the high-mounted rear wing technology developed for the open 2E Can-Am car to the closed-cockpit endurance formula. One of the original 2D chassis was converted to 2F specification during the season after retiring from the 1967 12 Hours of Sebring. The 2D's mechanical difficulties across both seasons illustrated the challenge of adapting a fundamentally American racing package to the demands of long-distance European competition.
The 2D represented Chaparral's first serious assault on international endurance racing and established Phil Hill as the team's primary European driver during this period. Its victory at the Nürburgring remains the highest outright result achieved by a Chaparral in the World Sportscar Championship. The car's development directly enabled the 2F, which carried Chaparral's aerodynamic innovations to a wider European audience and contributed to the proliferation of wings in Formula One from 1968 onward.