Manley 290730RX SBC 355ci Rotating Assembly 3.480" Stroke 4.030" Bore Flat Top Pistons

The Manley 290730RX is a complete rotating assembly engineered for Small Block Chevy (SBC) 355ci applications, built around a 3.480" stroke and a 4.030" bore (+.030" oversize).

Key Features:

• 4340 Forged Steel Crankshaft — Heat treated, stress relieved, shot peened, nitrided, and 100% magnafluxed for maximum durability
• H-Beam Connecting Rods — 6.000" rod length I-beam design with 7/16" ARP cap screws
• 2618 Forged Aluminum Platinum Series Pistons — Flat top design with -4cc dish; compatible with 11.2:1 compression with 58cc heads, 10.4:1 with 64cc heads, and 9.1:1 with 76cc heads
• Premium Chrome Moly Wrist Pins — Included with pistons for precise pin fit
• High Performance Piston Rings — 1/16", 1/16", 3/16" ring package included
• Clevite® "H" Series Narrowed Rod Bearings and "P" or "H" Series Main Bearings — High-performance engine bearings included
• Horsepower Rated — 750 hp with ARP 8740 cap screws; up to 1,500 hp with optional ARP 2000 cap screws
• Unbalanced Assembly — Precision external balancing recommended; order Manley P/N 04000-1 for balancing service within 5 grams

The "RX" suffix denotes the upgraded ARP 2000 cap screw specification, making this assembly suitable for high-boost and high-horsepower builds. This kit simplifies the engine build process by providing all critical bottom-end rotating components from a single performance manufacturer, ensuring matched tolerances and compatibility throughout.