Sirmac was the brainchild of Bernard Boyer who would later find fame as the designer of a number of cars for Matra including their F1 models, notably the F1 Championship winning MS80 (with Gérard Ducarouge), as well as their F2 cars and Le Mans winning sports cars. In the 1960s Boyer built a very neat looking F Junior car, it had a tubular chassis with cast light-alloy wheels and was powered by a 1100cc Renault Dauphine engine, and although the car was underpowered it gained a reputation for good handling. It is almost certain that the cars that appeared in F3 where converted F Junior chassis.
The Renault-powered Sirmac appeared at the beginning of the 1964 season taking 5th (3 laps down) at Pau and then seemed to vanish. There seems to have been at least two 1965 Sirmacs, the Ruata car was a Simca powered device whilst the Cassas model used a Renault engine. Both took part in a couple of early season Italian and French races in 1965, Frenchman Ruata failing to qualify for his two events, his compatriot scoring a DNF on his lone outing.
Denis Cassas, Frank Ruata.