The S14 has seen various iterations from BMW M such as the S14B23 EVO 2 with 217 horsepower (with no cats) and the S14B25 EVO 3 with 238 horsepower. Compare this to the Honda F20C that came with 240 horsepower from the 2.0 liter four-cylinder and also modern technology such as variable valve timing and the S14 look even more impressive.
People still race the S14 in various series and competitions today and VAC Motorsports gets customers all over the world asking for builds. What you see below is essentially an S14B27 which means a 2.7 liter version of the motor. It also features Schrick cams and a VIPEC ECU. This is a pump gas build so it is hardly the extreme side and still streetable.
The dyno overlay below shows the difference in output between 2.7 liter S14 with Schrick 284/276 cams and 50/50 header, a 2.5 liter S14 with the same cams and DTM header, and a 2.3 liter S14 with the same Schrick cams and a 50/50 header.
Peak output between the 2.5 and 2.7 liter only differ by 3 wheel horsepower. Fortunately the Mustang dynograph shows average horsepower and torque and the 2.7 liter shows an average gain of 16 wheel horsepower over the 2.5. The torque figures shows an average gain of 18 pound-feet at the wheels. Comparing the 2.7 liter to the 2.3 liter shows average horsepower gains of 37 wheel horsepower and 36 pound-feet of torque. Not bad for a naturally aspirated four-cylinder from the 1980's right?
Keep in mind this is a Mustang dyno and VAC does not play with the numbers so on a Dynojet output would rise close to 250 wheel horsepower naturally aspirated on pump fuel. The S14 continues to show it is a hell of a motor and VAC certainly can help you get big power and torque out of it.