The story of the Mercedes-Benz 190E 2.3-16 and 2.5-16 kicked off when Mercedes decided its new compact saloon, the 190, with its low-drag body and fancy multi-link rear suspension, would be the ideal base for a rally car. But to trump the likes of the BDA-powered Ford Escorts it needed more oomph. So in came Cosworth who designed a new cylinder head, and a few other bits to create a twin-cam 16-valve competition engine. As per the rules of the time, a homologated road-going version would be also need to be built to allow the rally car to be eligible to compete.
Then Audi arrived on the rally scene with the four-wheel-drive, turbocharged Quattro, and the rear-drive 190 Cosworth became obsolete before it got to play in the dirt. Mercedes-Benz persisted with the road car and launched the 190E 2.3-16 in 1983, and turned its competition aspirations to Group A circuit racing.
In 1987 the Cosworth was updated. The engine was enlarged to 2.5 litres (hence the badge 2.5-16) by increasing the stroke, and a new crank, conrods, pistons and reprofiled camshafts saw an extra 22 horsepower and 5Nm of torque. The purpose of the update was to better suit the Cosworth with Mercedes’s luxury and sophistication values.