SUBARU EJ20 HEAD/ EJ25 BLOCK ULTRA

JE Ultra Series pistons combine all of the best, most desirable piston features, such as thermal barrier crown coating, lateral gas ports, thick-wall wrist pins, and a revolutionary new forging technology for the ultimate in strength. They are ready for massive power and boost right out of the box. Features of the JE Ultra Series pistons: * Grain flow optimized 2618 forging * Lateral gas ports improve ring seal * Ceramic crown coating—thermal barrier blocks combustion heat for durability and better exhaust scavenging characteristics * Perfect Skirt Coating—protects skirts, reduces friction, and eliminates cold-start piston slap and false knock on computer-controlled engines * Accumulator grooves reduce ring flutter at high rpm * Double broach pin oiling * Upgraded 9310 pins and locks—thicker, premium material wrist pins boosts strength * Carbon steel nitride rings