Set of 4 big bore cylinder and forged iron piston set for 356 Pre-A (1950-1955) models with a 3 piece engine. The liner has aluminum fins over the forged iron and the piston is a JE forging with three rings. Pistons are balanced within 1g and have a late 30-degree dome. Earlier piston heads will need a flycut. 1,00mm copper spacers are included so that you have about 9:1 CR.