Just because it’s a four-cylinder engine doesn’t mean it isn’t potent. The S14B23, the E30 M3’s engine, is a standard-layout dual-overhead-camshaft inline four-cylinder. It’s naturally aspirated, which means it did not use a turbocharger or a supercharger. With 2.3 liters of displacement, this potent engine put out a whopping 197 horsepower. For reference, that’s about the same power output as the 302-cubic-inch V8 found in an equivalent-year Foxbody Mustang.
Vinauto reports that the engine was based on the BMW M10 four-cylinder engine block with the cylinder head from a BMW S38 six-cylinder (the M5 engine) with two cylinders removed. This engine was specifically developed for high-performance applications on both the road and the race track.
One of the most outstanding features of the S14 engine found in the BMW E30 M3 is its use of two individual throttle bodies. This allowed more precise tuning of the air intake system and provided a more rapid throttle response. This was a big contributing factor in the responsive and sporty feel of the first-gen M3 that gained the car its critical acclaim and enthusiasts’ praise.
