What is the actual hp of a 383 engine in a 1969 roadrunner?

Answer 1

Do you want gross hp, net hp or wheel hp? :)

Answer 2

The actual answer depends on how you measure it, as the other responder stated, and a myriad of other influences such as body style, engine modifications, engine accessories, presence of outside air intake, altitude and air temperature. During the muscle car era, auto manufacturers routinely understated the gross horsepower of their engines. The stated factory net horsepower for the 383cid engine in 1969 was either 330 or 335. As I remember, the only significant difference was that the 335hp engine had a dual point distributor. As a rule-of-thumb I have heard, the net horsepower is about 65-75% of the gross horsepower.