Forged parts (in this case pistons) are produced by heating and softening aluminum (or other material) and using pressure to shape it. Forged pistons are extremely durable, provide good resistance to detonation and are well suited to high-rpms. Forged pistons are stronger than cast pistons since the aluminum has been squeezed and the particles are forced closer together during the process, making the material more dense and stronger. This means less material is required and therefore the piston becomes lighter.
