Why does Audi use cast iron cylinder blocks?
2 Answers
Because cast iron cylinder blocks have stronger thermal load capacity, more mature technology, greater cylinder block strength, higher durability and reliability, larger adjustable limits, and greater potential. Cast iron engines exhibit excellent heat resistance, demonstrating far superior stability compared to aluminum engines during high-temperature, high-speed driving. Below are relevant introductions about cylinders: Introduction to Cylinders: In pneumatic transmission, cylinders are pneumatic actuators that convert the pressure energy of compressed gas into mechanical energy. There are two types of cylinders: those performing reciprocating linear motion and those performing reciprocating swinging motion. Cylinders performing reciprocating linear motion can be further divided into four types: single-acting, double-acting, diaphragm-type, and impact cylinders. Function of Cylinders: To convert the pressure energy of compressed air into mechanical energy, driving mechanisms to perform linear reciprocating motion, swinging motion, and rotational motion.
Once when chatting with a friend about Audi engines, he said, 'Cast iron blocks are so heavy, why not use aluminum ones?' I pondered that Audi engineers actually have a sharp eye. The biggest advantage of cast iron is its ability to withstand high temperatures and pressures, especially in turbocharged high-performance models where cylinder pressures skyrocket—cast iron remains as steady as Mount Tai without deformation. Friends who are into modifications know that the EA888 engine's cast iron block is excellent for squeezing out power; you can easily flash a Stage 1 tune without worrying about the block giving way. Cost-wise, cast iron is also significantly cheaper than aluminum alloy, after all, Audi has many entry-level models to consider in terms of cost. Moreover, in terms of thermal expansion properties, cast iron controls gaps better under high-load conditions, reducing the likelihood of oil burning. Lastly, let's not forget that cast iron has excellent sound insulation—the idle sound of the engine is even more robust than that of aluminum.