What is the torque rating of a 1974 Chevy small block 400?

There isn't a single torque rating for a 1974 Chevy small-block 400. The torque output varied depending on the specific engine configuration and the application (e.g., passenger car, truck). The advertised horsepower and torque varied significantly even within the same model year.

To find a more accurate torque rating, you would need to know the specific engine code (found on the engine block itself) or at least the vehicle it was installed in (model, trim level). This would allow you to look up the factory specifications in resources like a Chevrolet parts catalog or a repair manual from that year.