Callies Engine Connecting Rod

Callies Connecting Rods: Race-Engineered Precision for Every Build

When it comes to high-performance engine building, few components are as critical — or as unforgiving — as the connecting rod. It bridges the piston and crankshaft, enduring massive tensile and compressive forces with every combustion event. Callies Performance Products has built its reputation on engineering engine connecting rods that meet the exact demands of professional and amateur racers alike, with a product lineup that spans street performance to all-out competition.

Two Flagship Families: Ultra and Compstar

Callies structures its connecting rod catalog around two primary families, each targeting a different level of build intensity.

The Ultra Series represents Callies' top-tier, made-in-America offering. Ultra connecting rods are produced from extremely clean TimkenSteel product formulated to Callies' exact specifications — proprietary steel forged in Trenton, Michigan, and manufactured entirely in their Fostoria, Ohio facility, making them 100% made in the USA. Callies developed the Ultra connecting rod with the design goal of an uncompromised strength-to-weight ratio. Within the Ultra family, several specialized variants address specific applications:

• Ultra H-Beam: Best suited for high-revving naturally aspirated applications and mildly boosted engines, these are a great option where moderate weight savings are being considered.
• Ultra Enforcer I-Beam: Designed with fortified tower flanges, Enforcer I-beam connecting rods are the ideal component for turbocharged and supercharged engines.
• Ultra XD: Designed for extra cam clearance on long-stroke applications, the canted fastening system allows the use of a larger base circle cam for increased valve train stability, more lift using the same base circle, or longer stroke.
• Ultra Assassin: Callies' line of diesel rods, the Assassin Series is near net as forged with minimal machining and fastened by high-alloy cap screws made specifically for severe duty service by ARP, with AMS 642 bronze alloy used within the wrist pin housing bore to eliminate deformation and extrusion.

Fastener quality is a hallmark across the Ultra lineup. Ultra connecting rods are fastened by high-alloy cap screws produced specifically for severe applications by ARP, and for high-RPM or extreme horsepower applications, Ultra rods are fitted with Custom Age bolts — high-strength alloy fasteners that provide unparalleled clamping strength and toughness.

Compstar: High-Value Performance Without Compromise

For builders who need proven performance at a more accessible price point, the Compstar Series delivers without cutting corners. Every Compstar connecting rod begins its life on the drawing boards of Callies' Fostoria, Ohio engineering team — Callies owns the forging dies, meaning the metallurgy and geometry are dictated by Callies' standards, not by a third-party supplier.

Produced from heat-treated and stress-relieved 4340 material, Compstar rods are fully machined with a shot-blasted stress-riser-free surface, with every detail of this highly stressed component carefully analyzed to maximize repeatability and dependability. CompStar 4340 steel H-beam rods feature ARP 2000 bolts carefully positioned for maximum pan rail clearance with additional stroker clearance designed into each rod.

Dimensional reliability is a key differentiator. Compstar rods maintain dimensional repeatability through use of a lengthy stress relief process and multiple re-torque processing. For builds pushing into power-adder territory, Compstar rods are also available in the Compstar Xtreme variant — when a build pushes past street performance into heavy-duty boost and high-RPM racing, the Xtreme delivers. The Compstar Xtreme utilizes the same proven 4340 material and ARP 2000 or L19 fasteners, with strength added by thickening the flanges of the H-beam and a reduced depth of cut toward the center of the rod, while non-essential weight is removed to keep the overall weight in check.

Why Engine Builders Choose Callies

Founded in 1989, Callies Performance is committed to staying ahead of the competition, using the latest in computer-aided solid modeling and CNC technology to manufacture connecting rods to exacting tolerances. Their broad platform coverage spans Small Block and Big Block Chevy, Ford Coyote/Modular, LS, Mopar/Hemi, Viper, diesel, and even import applications like Honda, Nissan, Subaru, and Toyota. Whether you're building a street-strip daily driver or a dedicated race engine, Callies' connecting rod lineup offers a precisely engineered solution for the task.