The Stratos was a very successful rally racing car during the 1970s and 1980s. It started a new era in rally racing as it was the first car designed from scratch for this kind of competition.
The bodywork was designed by Bertone and loosely based on a (Lancia Fulvia V4 powered) concept car called Lancia Stratos 0 first shown at the Turin Motor Show in 1970. The body was wedge-shaped, and unusually short and wide, providing maximum traction.
However the final version of the Stratos was very different from the concept car. It had a distinctive crescent-shaped wrap-around windshield providing maximum forward visibility with almost no rear visibility (which was unnecessary for rallying anyway), and the engine was a mid-mounted 190 bhp (140 kW) 2418 cc Dino Ferrari V6.
Lancia did extensive testing with the Stratos and raced the car in several racing events where Group 5 prototypes were allowed during the 1972 and 1973 seasons. Production of the 400 cars required for homologation in Group 4 were launched in 1973 and the car was homologated for the 1974 World Championship. The Dino V6 was phased out in 1974, but 500 engines among the last built were delivered to Lancia.
For racing, the engine was tuned up to 280hp and even to 480hp with a turbocharger. However, turbocharged versions were only allowed to compete in Group 5 and were never as reliable as their naturally aspirated counterparts.
The car won the 1974, 1975 and 1976 championships in the hands of Sandro Munari, and might have gone on to win more had not internal politics within the Fiat group placed rallying responsibility on the Fiat 131 Abarths.
Without support from Fiat and despite new regulations that restricted engine power the car would remain a serious competitor and proved able to beat works cars in several occasions when entered by an experienced private team with a talented driver. The final point to the Stratos racing career at international level took place as late as 1981, at the Tour de Corse Automobile, a World championship event, with a victory of Bernard Darniche.
When the Fiat group favored the Fiat 131 for rallying Lancia also built two Group 5 turbocharged 'silhouette' Stratos for closed-track endurance racing. Theses cars failed against the Porsche 935s on closed tracks but proven successful in hybrid events. While they failed in the Tour de France Automobile, one of this cars won the 1976 Giro d'Italia Automobilistica, an Italian counterpart of the Tour de France Automobile. Unfortunately one of the cars was destroyed in Zeltweg, when it caught on fire due to engine overheating problems and the other surviving car would win the Giro d'Italia event again before it was shipped to Japan to compete in the Fuji based Formula Silhouette series, which was however, never raced. The car would then be sold on and reside in the Matsuda Collection before it then being sold on the renowned collector of Stratoses, Christian Hrablek, also the founder-designer of Fenomenon.
- In the original incarnation of the Transformers action cartoon series, Autobot Wheeljack transformed into a rally Stratos.