The 283 came in the same "high torque" format as did the 327`s. These aren`t made for horsepower, they are made for exactly as they say, Torque. They have small 1.71 intake valves and small runners which makes for high velocity at low RPM which makes it have immediate throttle response and high torque, when it reaches about 3500 RPM it`s out of breath. I`m not sure about the horsepower rating but I would guess it`s around 220.