At what RPM does the Volvo Penta D4 - 260 engine operate at its rated horsepower?

The Volvo Penta D4 - 260 engine reaches its rated horsepower at 3,500 RPM. This means that at this specific engine speed, the engine operates optimally to deliver the maximum power output it is designed to produce.

Understanding the importance of RPM (revolutions per minute) in relation to horsepower is crucial in maritime applications since it helps in determining the performance and efficiency of the engine in various operational scenarios. Operating at the rated RPM allows for optimal fuel efficiency and prevents undue strain on the engine components.

It's also worth noting that the other options reflect RPM levels that would either underperform or exceed the efficient operating range of the engine, potentially leading to decreased power output or mechanical issues.