It was originally developed for use with an Alfa Romeo turbo power plant but prior to the start of the season, Ligier lost the use of the engine.

Redesignated the JS29B, it scored a single point during the season when driver René Arnoux finished 6th in the Belgian Grand Prix.

It was reported at the time that Fiat, who had just bought Alfa Romeo that year, did not want involved in Formula One as a competitor to Ferrari, which at that stage they also part-owned.

However, following Arnoux's unfavourable comments, and Fiat's withdrawal, this meant that the team had no engine with which to compete until the second race in San Marino.

While the JS29 was originally designed for the 4-cylinder Alfa engine, it wasn't simply a case of slotting in the replacement Megatron 4-cylinder in its place.

At the next race, the Belgian Grand Prix, both cars were classified with Arnoux in sixth place for the team's sole point of the year.