How many cc's in a 350 cc motor bored 20 over?

A 350 cc motor that is bored 20 over will have its cylinder diameter increased by 20 thousandths of an inch. This typically increases the engine's displacement by approximately 1-2 cc, depending on the specific engine design and the amount of material removed. Therefore, the new displacement would be around 352-355 cc, depending on the exact increase from the bore.