OPEL ASCONA 400

Cosworth devised a 16-valve head for Opel’s Group 4 rally car in 1979, but the firm wanted more power and punched out the 2.0E block to 2.4 litres via an overbore and use of the crank from the cam-in-head 2.3 diesel, resulting in a claimed 340bhp. The Ascona 400 was the last rear-wheel-drive rally car to win the Drivers’ World Championship, with Walter Röhrl in 1982.