Power Piston for YFZ350 Banshee 87-06 in either cast or forged aluminum can provide a possible 6 HP gain in mid-range. Superstock Power Piston for YFS200 Blaster 88-06 in either cast or forged aluminum can provide up to 5 HP gain in mid to top range on stock to mild ported engines. Superstock Power Piston for YFZ350 Banshee 87-06 in forged aluminum for stock to mild ported engines and can reach possible top end gains of 6 to 8 HP. Big Bore Super Stock Piston for YFS200 Blaster 88-06 in cast aluminum: 240cc/72mm bore. Big Bore Power Piston for YFZ350 Banshee 87-06 in cast aluminum: 404cc/68mm bore.