2.2 pistons are cast, they hold up fairly well to modest detonation. Even forged will break if rattled hard enough. Warning- Stay far away from hyperutectic pistons if running forced induction. If running a low buck forced induction application the factory cast slugs will do, when in doubt check the Dakota forums where guys have been running them for years with blowers. The tune is everything, I ran in excess of 30 psi on cast factory pistons. Proper fuel ratio is always a must along with proper spark advance/retard. Edit- I would stay away from heavy pistons, they place excessive stress on the pins and rods. There is no shortage of stout forged slugs that are light and strong, much better than the old TRW pieces.
