0.020 Oversize Piston Assembly for High-Performance World Formula BuildsPush boundaries with the 0. 020 Piston Assembly (SKU 557123), engineered to exploit bored out World Formula cylinders for superior displacement. Expanded 3. 145 inch diameter for 2. 5% volume increase Hard anodized dome resists detonation under lean mixtures File fit rings for custom gap settings Offset wrist pin reduces skirt slap noise Full floating design for easy rod service Standard pistons cap your output; this one unleashes it by filling every