This item is for eight (8) .030-in. over bore Speed Pro (Sealed Power) forged coated skirt pistons and a moly piston ring set (Hastings/MAHLE) for 1970-1976 Buick 455ci big block V-8 engines. P/N (8) L2353AF-030 + 2M645-030. These pistons are Speed Pro's forged version of the higher compression 1970 year model pistons but can be used as a performance upgrade in other engines.

Speed Pro forged pistons are made from extruded VMS-75 aluminum alloy that is forged under 3,000 tons of pressure to "near-net" shape. After that, they are machined to their final configuration. These pistons offer excellent strength and durability and are capable of taking the punishment that is dished out on the street and in competition.

PISTON SPECIFICATIONS

• Bore: 4.342 in. (at .030 bore)
• Stroke: 3.900 in. (stock)
• Connecting Rod Length: Stock; rods NOT included
• Piston Top Style: Dish with no valve reliefs
• Piston Top Shape: .156 in. deep with 3.72-in. diameter
• Piston Head Volume: +27.8cc
• Compression Height: 1.975 in.
• Piston Material: Forged aluminum
• Wrist Pin Diameter: .9996 in.; pins included
• Wrist Pin Style: Press-fit only
• Ring Land Sizes: 5/64-5/64-3/16 (oil ring); rings included
• Notes: DurOshield coated skirts
• Usage: Street and mild strip; up to 150HP nitrous
• RPM Range: Idle - 6,500
• Compression Ratio (approximate): 9.16:1 w/66cc; 8.96:1 w/69cc; 8.43:1 w/77.5cc