What are the hazards of running a car engine at 4000 RPM?
2 Answers
The hazard of running a car engine at 4000 RPM is significantly shortening the engine's lifespan. Pros and cons of running at 4000 RPM: When accelerating to overtake, temporarily increasing the RPM to 4000 to obtain maximum torque won't damage the engine. In fact, it can help remove carbon deposits from the engine to some extent, which benefits the engine. However, if the engine is frequently kept at around 4000 RPM, its lifespan will be substantially reduced. Conditions for 4000 RPM not harming the engine: Since 4000 RPM is generally around the peak torque or maximum power RPM range, there's a prerequisite for high RPM operation not damaging the engine - the coolant temperature gauge must reach about 90°C. Immediately revving the engine to 4000 RPM after startup is most harmful to the engine.
Driving at high RPMs up to 4000 is actually quite common, especially during acceleration or uphill climbs. I personally got used to doing this with manual transmission cars. However, there are several downsides: First, engine wear increases significantly—high RPMs intensify friction between components, accelerating damage to parts like pistons and valves, which can lead to costly repairs over time. Second, fuel consumption spikes dramatically, burning up to 20% more fuel for the same distance, which hits your wallet hard. Additionally, the increased noise and vibration make the ride uncomfortable, especially on long trips where fatigue doubles. Worse yet, if the car's condition is poor or maintenance is neglected, it may cause excessive lubricant temperatures, leading to component burning or even breakdowns. It's advisable to avoid flooring the throttle frequently. For instance, maintaining around 2000 RPM at 60 km/h strikes the best balance between economy and safety. Developing this habit can significantly extend your vehicle's lifespan.
