The numbers and graphics on a diesel engine specification sheet describe the power, torque, torque rise and fuel consumption of the engine. Most sheets show measurements in both SI metric units and older SAE units.
In North America, most diesel engines are still described by their horsepower outputs. Electrical output is typically described in kilowatts. Specification sheets may show up to five power output ratings for an engine to comply with DIN, SAE or JIS standards. Vehicles with higher horsepower engines require more support and maintenance to maintain the engine's life. It is important to consider the vehicle's purpose when considering horsepower. Automotive engines are usually smaller and lighter than other engines.
While horsepower measures the rate of work, torque measures the rotary force of the engine. There is a fixed relationship between the two variables, but the torque rise affects this relationship. The number of cylinders and length of the piston strokes affect the torque rise and therefore the torque. Engines with more torque rise perform work at a faster pace.
Specification sheets also include fuel curves that demonstrate the rate of fuel consumption of the engine. Factors such as minimum cetane rating and ambient conditions have an effect on these curves.