CUMMINS NTA855 1800 RPM Big Cam Diesel Engine

The Cummins NTA855 with Big Cam designation and 1800 RPM rating is a rugged, heavy-duty industrial diesel engine designed for demanding power applications where durability, torque, and reliability are critical. Part of Cummins legendary 855 cubic-inch (14 L) family, the NTA855 series combines proven engineering with robust construction and versatile performance — making it a preferred choice for many marine, industrial, and power generation uses around the world.

Built to thrive under continuous load, this engine is engineered with a turbocharger and after-cooler to optimize combustion efficiency, boost power density, and reduce specific fuel consumption. The Big Cam variant refers to a camshaft and valvetrain configuration tailored for improved torque characteristics and durability in heavy duty service. Engineered for 1800 RPM operation, it delivers smooth, dependable power where steady rotational speed and strong low-end torque are required.

Constructed with a cast iron block, heavy-duty forged crankshaft, and precision ground components, the NTA855 Big Cam emphasizes long service life and ease of maintenance under harsh operating conditions. Its robust cooling system and efficient fuel delivery system ensure stable thermal performance and reliable operation even in high ambient temperatures.

The CUMMINS NTA855 1800 RPM Big Cam engine is widely used across marine propulsion systems, auxiliary power units, industrial drives, agricultural equipment, and generator sets. With strong aftermarket support and global parts availability, it remains a dependable workhorse for businesses that require consistent performance, serviceability, and long-term support.

Whether installed on a vessel, in a heavy equipment application, or connected to a generator set, the NTA855 Big Cam 1800 RPM engine represents a balance of proven durability, efficient operation, and adaptable performance for users in diverse industries.

Technical Specifications

General Engine Data

• Engine Type: 4-stroke, inline 6-cylinder diesel

• Displacement: 14.0 liters (855 cubic inches)

• Bore × Stroke: 140 mm × 152 mm

• Aspiration: Turbocharged & Aftercooled (T/A)

• Fuel System: Cummins PT (Pressure-Time) direct injection

• Rated Speed: 1800 RPM

• Compression Ratio: Approx. 14.0–14.5:1 (varies by build)

• Rotation: Counterclockwise (facing flywheel)

Performance (Typical 1800 RPM Ratings)

• Power Range: 330 – 400 HP (246 – 298 kW) depending on configuration

• Typical 350 HP Rating: 350 HP (261 kW) @ 1800 RPM

• Peak Torque: Approx. 1350 – 1550 Nm (varies by rating)

• Designed for continuous heavy-duty operation at constant speed

Physical Specifications

• Dry Weight: Approx. 1,400 – 1,500 kg (engine only)

• Configuration: Cast iron block & head

• Cooling System: Water-cooled

• Lubrication System: Full-flow oil filtration

Key Features

• Big Cam camshaft design for improved durability and torque output

• Strong low-end torque for heavy load applications

• Reliable mechanical fuel system (easy maintenance)

• Suitable for generator sets, marine propulsion, industrial drives, and heavy equipment