Callies 5UO-31V-AS Ultra Forged 4340 Steel Crankshaft 4.000" Stroke

The Callies Ultra Series 5UO-31V-AS is a premium forged crankshaft designed for high-performance engine builds demanding maximum strength and durability. Precision-machined from 4340 forged steel, this crankshaft delivers exceptional reliability under extreme loads and high RPM conditions.

Key Features:

• 4340 forged steel construction for superior strength and fatigue resistance
• 4.000-inch stroke for increased displacement and torque output
• Ultra Series design with optimized counterweight configuration
• Precision-ground journals with micropolished surfaces
• Nitrided surface treatment for enhanced wear resistance
• Magnetic particle inspected to ensure material integrity
• Suitable for forced induction and naturally aspirated applications

Callies Performance Products has built a reputation for manufacturing some of the strongest crankshafts in the industry. The Ultra Series combines proven metallurgy with advanced manufacturing techniques to deliver a crankshaft that can withstand the rigors of racing, street performance, and extreme power applications. Each crankshaft is individually balanced and inspected to meet Callies' exacting quality standards.