A forged engine is an engine where some of the metallic parts have been made via the forging process as opposed to casting for improved strength. Forging is a process where hot metal of the rough shape is then very forcibly squished by exact shape dies, severely compressing the metal and creating a denser, stronger part. In contrast, casting is the process of pouring molten metal into a mold and letting it cool. Forged engines have all forged internal components such as the crank, rods, and pistons, which are much stronger than cast components. The difference between boring and stroking an engine is that boring makes the hole the piston travels a larger diameter, while stroking changes the crank to one that has a longer length stroke. The benefits of a forged engine include improved strength and reliability, which is especially important for high-performance engines that are subjected to high boost pressures.