The N-code 383 is the four-barrel high-performance variant of Chrysler's B-block 383. Period rating: 335 horsepower gross at 5,200 rpm, 425 lb-ft of torque at 3,400 rpm. It was the standard engine on the 1970 Super Bee and Road Runner and the base big-block on most Charger R/T and GTX configurations.
Compared to the Six-Pack, the 383 four-barrel is the engine most period road tests treated as the practical baseline: not as quick, but lighter on the nose, more amenable to small carburetors and stock cams, and dramatically less expensive to feed. A clean-running N-code car is not slow.