What are the differences between the S50 and S52 engines?
The North American-spec powerplant, known as the S52, is based closely on the regular production M52 six-cylinder engine. Like that motor, it has a cast iron block, aluminum cylinder head and four valves per cylinder, with two-stage VANOS variable valve timing on the intake strokes. Unique to the S52, however, is a larger bore of 86.4mm and a longer stroke of 89.6mm for a total displacement of 3,152cc. The engine is rated at 240 hp (SAE) at 6,000rpm and 236 lb/ft of torque at 3,800 rpm. In addition to the larger displacement, the S52 utilizes the following special M components (compared to the M52): -Ported and polished cylinder head -Retuned VANOS variable valve timing for greater high-rpm power -Heavy-duty valve springs -More finely balanced camshafts -Valve lifters, springs and spring seats with reduced mass -Free-flowing intake and exhaust systems The European-spec powerplant, known as the S50 B32, is a much more exotic unit. Like the S52, it also contains an iron block and aluminu
