VAUXHALL XE20

The famous XE20 ‘red top’ twin-cam cylinder head was designed by Cosworth to fit on to Opel’s ‘Family II’ engine block that had appeared in 1979 as a cam-in-head design. From 1987, it made the 150bhp Astra GTE 16v (right) a classleader in performance, and it later appeared with a turbo in both the Calibra and Vectra. As well as powering the Caterham HPC (on Webers, with c200bhp), this versatile unit has been adopted by rallyists as a popular and cheap power source for Mk2 Escorts. Technically, the ‘red top’ is only a true Cosworth until 1991, when the Coscast heads were replaced by Gm-branded items from Kolben-schmidt, which suffered porosity issues.