The first of the 126 series was tested by Gilles on September 9th 1980 at Imola,  efore the Italian GP. The Ferrari 126C was the team's first attempt at a turbocharged F1 car, it was designed by Mauro Forghieri and Harvey Postlethwaite and used between the 1981 and 1984 seasons. Still, the turbo engine did not make its debut until 1981 at the Qualifying of the GP Long Beach with the 126 CX (also included in this collection).
Comprex vs Turbo
The Ferrari 126C was designed to replace the highly successful but obsolete 312T series in use since 1975. The basic chassis was almost identical to the previous car but the smaller and narrower V6 engine with forced induction, better suiting the ground effect aerodynamics now needed to be competitive (the previous car's wide flat-12 boxer engine obstructed the airflow necessary to generate efficient ground effect), and was a better package overall. During engine development Ferrari started experimenting with a Comprex pressure wave supercharger, supplied by a Swiss company; this car version was initially called 126BBC from the name of Brown Boveri Comprex and later named 126CX. The system was praised by drivers for driving like a naturally aspirated engine but having an extended power range, thus eliminating the notorious lag of the turbocharger. However the system was rather tall in the car and there could be some mixing of exhaust and intake gas so the team opted for the fitment of twin KKK turbochargers producing around 600 bhp (447 kW; 608 PS) in qualifying trim, detuned to 550 bhp (410 kW; 558 PS) in race trim. The car fitted with turbochargers was called 126CK.[4]
Enzo Ferrari had hired Nicola Materazzi in December 1979 to work with Forghieri and Tomaini and specifically for his experience with the turbocharging in the Lancia Stratos Gr 5 Silhouette cars. He would bring technical know-how in the team to match the knowledge that Renault had built over time. Materazzi thus saw the advantages of the comprex system but also its difficulties and prepared also a second iteration with two smaller Comprex systems driven by hydraulic clutch instead of a belt but this was not used since the turbocharger was deemed simpler and worth pursuing. Hence Materazzi proceeded to perfect the following iterations of powertrain to obtain increased power and reliability
The 126CK was first tested during the Italian Grand Prix in 1980. In testing it proved far faster than the 312T5 chassis the team were then using and Gilles Villeneuve preferred it, though he had reservations about the handling

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