The car had a frame made of square steel tubes with glued and riveted aluminium paneling.

The suspension was equipped with a torsion bar on both axles, the Hewland F.G.400 gearbox flanked the rear brakes.

The engine was the two-liter 4-cylinder Abarth type E, twin-shaft, four valves per cylinder, and Lucas injection, 270 hp at 8,700 rpm increased to 285 in the G version.

Further tests were carried out in Fiorano and the last tuning, in Vallelunga, led Merzario to obtain very promising times.

At the wheel of the Abarth-Osella PA1 in 1973, in addition to Arturo Merzario, also Vittorio Brambilla, Nanni Galli, Dieter Quester, Giorgio Pianta, Jean-Claude Andruet, Henri Pescarolo, Derek Bell, Franco Pilone, Juan Fernandez, Pino Pica, Francisco Torredemer and Christian Melville who took the Abarth team to third place, behind Lola and Chevron.