When it comes to performance enhancement in four-stroke engines, the focus first turns to the cylinder heads. This is where the mixture supplied by the carburetor or injection is converted into pure horsepower. Understanding the functional relationships of the individual components of the cylinder head is key to achieving high performance, reliability, and efficiency in any four-stroke engine, whether on the road or in motorsport. This volume of the practical handbook series describes in detail, with the help of numerous images and illustrations, the theoretical foundations of cylinder head technology and then explains possible steps for performance enhancement. All components are examined separately - from the intake and mixture formation to ignition, exhaust, and the exhaust system. Presented in an easily understandable manner.