FHR PISTON KIT BBC 489

Icon's FHR (Formed Head Relief) pistons offer quality for specific engine builds. They feature valve reliefs formed during the forging process, and many dome pistons have a solid dome for custom compression ratio machining. Made from 11% silicon 4032 aluminum, FHR pistons allow for tighter piston-to-wall clearance, reduced friction, extended life, and decreased wear. Key features: Mini grooves for heat transfer in overheated conditions. Skirts machined by UEM's in-house CNC machines. Die-formed relief valves. Accumulator groove for ring seal and flutter elimination. Wrist pins and spiral locks included. Rings (5/64" x 5/64" x 3/16") are not included. Compression Ratio: 10.2:1 (96.5cc), 9.5:1 (105cc), 8.6:1 (119cc). Advertised piston weight: 527 grams; wrist pin weight: 141 grams. OE Deck Height: 9.800". Standard bore size: 4.250". Centered Pin.