The 1966 World Sportscar Championship season was the 14th season of the FIA "World Sportscar Championship" motor racing.[1] It featured the 1966 International Manufacturers' Championship and the 1966 International Sports Car Championship,[1] which were contested between 5 February 1966 and September 11, 1966, over a total of thirteen races.[2] The International Manufacturers' Championship was open to Group 6 Sports-Prototypes and was contested in two engine capacity divisions, P1 (Up to 2000cc) and P2 (Over 2000cc).[3] The International Sports Car Championship was open to Group 4 Sports Cars and was contested in three engine capacity divisions, S1 (Up to 1300cc), S2 (1301 to 2000cc) and S3 (Over 2000cc).[3]
The 13 championship races each counted towards one or more of the five divisions.[3]
Both championships scored points to the top six competitors in each class, under four different tables or Baréme'. Baréme I corresponded with the old order of 9-6-4-3-2-1. Baréme II was in the order 10-7-5-4-3-2. Baréme III, valid only for Le Mans, was in the order 12-9-7-5-4-3. Baréme 0, valid only for the Grosser Bergpreis der Schweiz, was half of Baréme I: 4.5-3-2-1.5-1-0.5. Constructors were only awarded points for their highest finishing car. Other finishers from the same manufacturer were merely skipped in the points count.[4]
Only the best 4 results counted towards the championship (5 in S3, 6 in S2). Points earned but not counted towards the championship total are listed in (brackets).
| IMC | ISCC S1 | ISCC S2 | ISCC S3 | Race | Circuit or Location | Date | |
|---|---|---|---|---|---|---|---|
| R 1 | - | R 1 | R 1 |  24 Hours of Daytona | Daytona International Speedway | 5 February 6 February | |
| R 2 | R 1 | R 2 | R 2 | 12 Hours of Sebring | Sebring International Raceway | 26 March | |
| R 3 | - | R 3 | R 3 |  1000km Monza | Autodromo Nazionale Monza | 25 April | |
| R 4 | R 2 | R 4 | R 4 | Targa Florio | Circuito delle Madonie | 8 May | |
| R 5 | - | R 5 | R 5 |  1000km Spa | Circuit de Spa-Francorchamps | 25 May | |
| R 6 | R 3 | R 6 | R 6 |  1000km Nürburgring | Nürburgring | 5 June | |
| R 7 | - | R 7 | R 7 |  24 Hours of Le Mans | Circuit de la Sarthe | 18 June 19 June | |
| - | R 4 | - | - | Mugello 500 km | Mugello Circuit | 17 July | |
| - | R 5 | - | - | Coppa Citta di Enna | Autodromo di Pergusa | 7 August | |
| R 8 | - | R 8 | - | Hockenheim 500 km | Hockenheimring | 14 August | |
| - | R 6 | R 9 | R 8 |  Grosser Bergpreis der Schweiz | Crans-Montana | 28 August | |
| - | R 7 | - | - | 500 km Nürburgring | Nürburgring | 4 September | |
| - | R 8 | R 10 | R 9 |  Austrian Sports Car Grand Prix | Zeltweg Airfield | September 11 |
Note: The Hockenheim 500 km race did not count towards the Over 2000cc division of the International Manufacturers Championship.[3]
| Position | Manufacturer | DAY | SEB | MZA | TGA | SPA | NÜR1 | LMS | HOC | Total [5] | |
| Over 2000cc | |||||||||||
| 1 | Ford | 10 | 10 | - | - | 6 | - | 12 | - | 38 | |
| 2 | Ferrari | (4) | - | 10 | 10 | 9 | 7 | - | - | 36 | |
| 3 | Chaparral Cars | - | - | - | - | - | 10 | - | - | 10 | |
| Up to 2000cc | |||||||||||
| 1 | Porsche | 10 | 10 | 10 | - | - | (5) | 12 | (9) | 42 | |
| 2 | Ferrari | - | 7 | (4) | 10 | 9 | 10 | - | - | 36 | |
| 3 | Alpine | - | - | - | - | 7 | - | 5 | - | 22 | |
| 4 | Austin-Healey | - | 3 | - | 5 | 2 | 3 | - | (2) | 13 | |
| 5 | Triumph | 7 | - | - | - | - | - | - | - | 7 | |
| 6 | Abarth | - | - | - | - | - | 4 | - | - | 4 | |
| ASA | - | - | - | 4 | - | - | - | - | 4 | ||
| 8 | Lotus | - | - | - | - | - | - | - | 3 | 3 |
| Position | Manufacturer | DAY | SEB | MZA | TGA | SPA | NÜR1 | LMS | MUG | PER | HOC | SCH | NÜR2 | ZEL | Total | |
| Division I (Up to 1300cc) | ||||||||||||||||
| 1 | Abarth | - | - | - | - | - | 10 | - | 9 | 9 | - | (4.5) | 9 | (9) | 37 | |
| 2 | Alpine | - | 10 | - | 10 | - | 4 | - | 4 | - | - | - | - | - | 28 | |
| 3 | Alfa Romeo | - | - | - | 3 | - | - | - | - | - | - | - | - | - | 3 | |
| Division II (1301 to 2000cc) | ||||||||||||||||
| 1 | Porsche | 10 | 10 | - | 10 | (6) | 10 | 12 | - | - | 9 | (4.5) | - | (9) | 61 | |
| 2 | Alfa Romeo | - | 7 | 10 | 5 | - | 3 | - | - | - | - | 1 | - | - | 27 | |
| 3 | Lotus | - | - | - | - | 9 | - | - | - | - | - | - | - | - | 9 | |
| 4 | Volvo | 3 | - | - | - | - | - | - | - | - | - | - | - | - | 3 | |
| Division III (Over 2000cc) | ||||||||||||||||
| 1 | Ford | 10 | 10 | 10 | 10 | 9 | (10) | - | - | - | - | - | - | (9) | 49 | |
| 2 | Ferrari | 5 | - | 4 | 7 | 3 | - | - | - | - | - | - | - | 4 | 23 | |
| 3 | Shelby | - | 7 | - | - | - | 4 | - | - | - | - | - | - | - | 11 |
The following models contributed to the nett points awarded to their respective manufacturers in the two championships.
International Manufacturers Championship - Over 2000cc
International Manufacturers Championship - Up to 2000cc
International Sports Car Championship - Division 1
International Sports Car Championship - Division 2
International Sports Car Championship - Division 3