"Torsk" was long, with a beam of and a maximum draft of . She displaced surfaced and submerged. The "Tench"-class submarines were powered by four Fairbanks-Morse Model 38D8-⅛ 10-cylinder opposed piston diesel engines driving electrical generators. These were rated at for a maximum speed of on the surface. During underwater operations, she was powered by two 126-cell "Sargo" batteries that drove two low-speed direct-drive General Electric electric motors. Her electric motors provided and a top speed of submerged. While surfaced, she had a cruising radius of at a speed of . Her submerged endurance was limited by the life of her batteries, which at a speed of , would be depleted after 48 hours. She could carry enough provisions for her crew of ten officers and 71 enlisted men for 75 days of operations.