GM LSx CS 4340 Forged Crank 3.625 Stroke

The CALLIES GM LSx CS 4340 Forged Crank with 3.625 Stroke is a premium forged steel crankshaft engineered for high-performance GM LS-series engine builds. This internally balanced unit features a 58X reluctor ring for seamless integration with modern engine management systems and utilizes a single-piece rear seal design for improved durability and simplified installation. Built from 4340 forged steel, this crankshaft is designed to handle the demands of forced-induction, naturally aspirated, and street-performance applications where reliability and strength are non-negotiable.

The 3.625-inch stroke is a popular mid-range displacement option in the LS platform, allowing builders to create engine packages between approximately 408 and 427 cubic inches depending on bore size. The internal balance approach simplifies rotating assembly weight distribution and eliminates the need for external balancing procedures, reducing downtime and cost. The 58X reluctor pattern is the standard for most LS engine control modules, ensuring plug-and-play compatibility with factory and aftermarket ECUs without custom tuning requirements or sensor modifications.

This crankshaft is ideal for LS engine builders targeting street performance, road racing, truck applications, or naturally aspirated builds where forged strength and proven reliability are priorities. The CALLIES name carries recognition in the high-performance engine building community for precision manufacturing and quality control. Whether building a restomod, performance truck, or dedicated street engine, this crank delivers the structural integrity needed for sustained power delivery and long-term durability in demanding service.

LS platform engines have become the foundation of countless modern performance builds due to their efficiency, aftermarket support, and versatility. A quality forged crankshaft is critical to engine longevity, particularly in boosted or high-rev applications. The CALLIES GM LSx CS 4340 represents a balance of proven engineering and manufacturing reputation in an industry where crank failure can result in catastrophic engine damage.