Complex sentence: The twin-cam, 16 valve, "aluminum" cylinder head design was assisted by Cosworth, but Chevrolet did the development work which features electronic ignition, Bendix electronic fuel injection, and stainless steel headers.
Split into simpler sentences: The twin-cam, 16 valve, "aluminum" cylinder head design was assisted by Cosworth, but Chevrolet did the development work. The engine features electronic ignition, Bendix electronic fuel injection, and stainless steel headers.