What are the advantages of cast iron engine blocks?
2 Answers
Advantages of cast iron engine blocks: Compact engine size and smaller volume. Below are the benefits of different engine block materials: 1. Aluminum engine blocks: Aluminum has a lower density than cast iron, making aluminum blocks slightly lighter while meeting strength requirements. A lighter engine can positively impact the vehicle's weight distribution, and the overall vehicle mass is also reduced. Therefore, aluminum blocks have an advantage in this aspect. However, aluminum alloy materials have inferior corrosion resistance and durability compared to cast iron, and cast iron offers better strength than aluminum alloy. 2. Iron engine blocks: Due to aluminum's lighter density, the structural strength per unit volume of aluminum is lower than that of cast iron, so aluminum blocks are usually smaller in volume. For example, the EA827/EA113/EA888 engine blocks have a cylinder center distance of 88mm, with some versions allowing a bore diameter of up to 82.5mm. After accounting for cooling water channels, the actual cylinder walls are quite thin. This results in a very compact engine with a small overall volume, an effect that is harder to achieve with aluminum blocks. In this regard, cast iron blocks have the advantage.
I used to drive trucks for long-distance hauling, and the cast iron engine blocks were incredibly durable, running for hundreds of thousands of kilometers without needing replacement. They have high strength, are less prone to deformation, and provide stable heat dissipation, so even after a full day of tough mountain driving, the engine rarely overheats—it’s worry-free. The overall cost is low, with high resale value in the used market, cheap repairs, and easy part replacements. Although they’re slightly heavier than aluminum ones, it doesn’t affect fuel consumption, and they feel solid on the road. The maintenance intervals are longer, extending the engine’s lifespan, which is crucial for drivers like me who frequently cover long distances—reliability is the top priority.
