The M127.II inline-six engine with and torque was based on Mercedes-Benz' venerable M180 inline-six with four main bearings and mechanical Bosch multi-port fuel injection. Mercedes-Benz made a number of modifications to boost its power, including increasing displacement from , and using a completely new cylinder head with a higher compression ratio (9.3 vs. 8.7), enlarged valves and a modified camshaft. A fuel injection pump with six plungers instead of two was fitted, which allowed placing the nozzles in the cylinder head and "shooting" the fuel through the intake manifold and open valves directly into the combustion chambers. An optional oil-water heat exchanger was also available.