GN6320 series marine diesel engine, developed by CSI Power (Ning Dong), is a four-stroke, inline, six-cylinder, non-reversible diesel engine. It offers a power range of 735 kW to 1618 kW and a speed range of 550 to 600 r/min. The bore and stroke are 320 mm × 380 mm, with a total displacement of 183.36 liters.
To accommodate various engine room layouts, both port and starboard main engine configurations are available. The turbocharger can be positioned at either the front or rear of the engine. For the same engine model, clockwise and counterclockwise rotations (viewed from the flywheel end) are available to match the propeller’s rotation direction.
All CSI Power marine engines fully comply with the IMO Tier II emission standards established by the International Maritime Organization (IMO).
| Engine Model | Rated Power | Rated Speed | Emission Standard |
| GN6320ZC2B | 735 kW | 600 r/min | IMO Tier II / Tier III |
| GN6320ZC3B | |||
| GN6320ZC4B | 1323 kW | 550 r/min | IMO Tier II / Tier III |
| GN6320ZC5B | |||
| GN6320ZC6B | 1323 kW | 600 r/min | IMO Tier II / Tier III |
| GN6320ZC7B | |||
| GN6320ZC12B | 1471 kW | 600 r/min | IMO Tier II / Tier III |
| GN6320ZC13B | |||
| GN6320ZC14B | 1618 kW | 600 r/min | IMO Tier II / Tier III |
| GN6320ZC15B |
