Ferrari's decision to develop a rear-mid-engined sports car came from recognising that rear-engined competitors were transforming both Grand Prix racing and sports car competition. Although Enzo Ferrari publicly denied in January 1959 that such a project was underway, he had privately tasked engineer Carlo Chiti during that same year with developing rear-engined solutions for both Formula One and sports car racing, to be ready by 1961. Chiti concluded that Vittorio Jano's existing 2.4-litre 65-degree Dino V6 was suitable for use in both applications, owing to its compact dimensions and light weight. Development proceeded through 1960 and into early 1961.
The resulting 246 SP chassis was a tubular space frame fabricated from round steel tubing by oxygen-acetylene welding, with durability for endurance racing prioritised over minimum weight. Fully independent double wishbone suspension was fitted at all four corners, using coil springs and Koni dampers — a layout directly derived from the concurrent 156 Formula One car. Dunlop disc brakes of 12-inch diameter were used front and rear, with the rear brakes mounted inboard at the transaxle.
The 246 SP's bodywork was a collaboration between Chiti and Medardo Fantuzzi of Carrozzeria Fantuzzi, with aerodynamic solutions tested in a wind tunnel. The resulting design featured a very low bonnet, high rear bodywork flush with the top of the windscreen, and a vertical tail fin. Most distinctive were two prominent air intakes in the front of the car, a solution concurrently adopted on the 1961 Ferrari 156 Formula One car (earning that car the "sharknose" nickname) and the 250 TRI61. During early testing, Wolfgang von Trips and Richie Ginther discovered the car was aerodynamically unstable at high speed, with the problem thought connected to a rollover crash at the Modena Autodrome. The vertical fin was removed and a 5-inch rear spoiler added — a solution suggested by Ginther based on his wartime aviation experience.
For 1962, revised bodywork was introduced on all Dino SP cars in response to FIA regulation changes, with lower windscreens and reduced rear bodywork height. The 246 SP's cockpit gained a reputation for extreme heat; von Trips reportedly remarked "You could grow tomatoes in the cockpit during a seven-hour race."
The engine was the Tipo 171S 65-degree Dino V6, with a total capacity of 2,417 cc from an 85 by 71 mm bore and stroke. Twin overhead camshafts per cylinder bank drove two valves per cylinder, with a compression ratio of 9.8:1. Fed by three Weber 42DCN carburettors, the engine produced 270 PS at 8,000 rpm. Lubrication was by a dry sump system with the oil reservoir and cooler located at the front of the car. Two engine short blocks were produced per chassis, with a single set of cylinder heads swapped between them as required.
The gearbox was a 5-speed transaxle designed by engineer Giorgio Salvarani, closely related to the unit used in the 156 Formula One car, incorporating straight-cut gears, a hydraulic multi-plate clutch, a ZF-type limited-slip differential, and inboard disc brake mounts.
The first chassis, serial number 0790, was presented at the February 1961 press conference. Its race debut came at the 12 Hours of Sebring, where Richie Ginther and Wolfgang von Trips led comfortably before a broken steering arm ended the run. Victory came at the 1961 Targa Florio, where the winning crew of von Trips, Ginther, and Olivier Gendebien completed the demanding Sicilian mountain circuit race outright. The same trio later finished third at the 1961 1000 km Nurburgring despite handling difficulties in cold, wet conditions.
At the 1961 24 Hours of Le Mans, Ginther and von Trips set the fastest practice lap but retired on the Mulsanne straight when the car ran out of fuel due to a miscalculation.
In 1962, chassis 0790 returned to competition under the NART banner at Sebring before Phil Hill and Olivier Gendebien took an outright victory at the 1000 km Nurburgring in May. Mike Parkes won the Guards Trophy at Brands Hatch in August, driving 0790 against Innes Ireland's Lotus 19.
The second chassis, 0796, contested the 1961 Targa Florio with Phil Hill and Olivier Gendebien but crashed on the opening lap. In 1962, chassis 0796 — now raced by the Rodriguez brothers and Gendebien with Willy Mairesse — won the Targa Florio outright, giving the 246 SP a second Targa victory and contributing to Ferrari claiming the "1962 Coupe des Sports" class title.
Only two 246 SPs were ever produced. Chassis 0790 was converted to 196 SP specification in early 1963. Chassis 0796 was used as a development mule for the V12-powered Ferrari 250 P, fitted with an extended chassis and 3.0-litre engine, before being destroyed in a crash. The 246 SP's mid-engine architecture directly informed the V12 Ferrari P-series sports prototypes that followed from 1963 onwards, making it a pivotal car in Ferrari's transition to the configuration that would dominate endurance racing for the rest of the decade.