Speedmaster Pontiac 455 4340 Forged Steel Crankshaft PCE276.1140 – ST-4.25 Stroke

The Speedmaster Pontiac 455 4340 Forged Steel Crankshaft (PCE276.1140) is a precision-engineered rotating assembly component designed for Pontiac 455 big-block engines. This crankshaft is forged from 4340 steel for strength and durability, with a stroke of 4.25 inches, main journal diameter of 3.25 inches, and rod journal diameter of 2.200 inches. The two-piece external balance design is optimized for both stock and modified engine configurations that require reliable, high-performance rotating assembly components.

This crankshaft is ideal for engine builders, restoration specialists, and performance enthusiasts rebuilding Pontiac 455 engines for street, classic car, or light-duty performance applications. The 4340 forged steel construction provides the toughness needed for sustained high-RPM operation. Compatible with Pontiac 455 engine blocks and matching rotating assembly components, it serves as a critical foundation for any Pontiac big-block build seeking to maintain authenticity or upgrade to modern performance standards.

Key Features & Benefits

• 4340 Forged Steel: Constructed from 4340 forged steel for superior strength and durability under load.
• ST-4.25 Stroke: 4.25-inch stroke designed for Pontiac 455 engine specifications.
• M-3.25 Main Journal: 3.25-inch main journal diameter sized for Pontiac 455 engine blocks.
• RJ-2.200 Rod Journal: 2.200-inch rod journal diameter for proper connecting rod fitment.
• 2-Piece External Balance: Two-piece external balance configuration optimized for engine balance requirements.

Specifications

Ideal Applications

• Pontiac 455 engine rebuilds and restorations
• High-performance and modified big-block builds
• Classic car engine assembly and upgrades
• Street and light-duty performance applications