Callies Ultra connecting rods are produced from extremely clean TimkenSteel product, that is formulated to our exact specifications. This proprietary steel is forged in Trenton, Michigan, and manufactured entirely in our Fostoria, Ohio facility, making them 100% made in the USA. Pride in workmanship, and attention to detail are qualities you’ll discover during careful examination of our finished product. Each step of the manufacturing history of every Ultra connecting rod is meticulously maintained by our manufacturing team. You can be confident of the material and workmanship of these quality components.
Ultra connecting rods are fastened by high alloy cap screws produced specifically for severe applications by ARP. For high RPM or extreme horsepower applications, Ultra connecting rods are fitted with Custom Age bolts. These high strength alloy fasteners provide unparalleled clamping strength and toughness.
Ultra Enforcer I-Beams: Designed with fortified tower flanges, Enforcer I-beam connecting rods are the ideal component for turbocharged and supercharged engines. The I-beam design has been time tested and proven as the most stable configuration in high torque applications. High combustion forces generated within boosted engines are capable of buckling a standard connecting rod that had been intended for a naturally aspirated application.
Ultra H-Beams: Ultra H beam connecting rods are best suited for high-revving naturally aspirated applications and mildly boosted engines. These are a great option for a competent con rod where moderate weight savings are being considered.
Ultra XD: These rods were 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. Assassin Series Rods are near net as forged with minimal machining. They are fastened by high alloy cap screws made specifically for severe duty service by ARP Inc. To eliminate deformation and extrusion only AMS 642 bronze alloy is used within the wrist pin housing bore.
Ultra Dirt / Oval: The Ultra Dirt rod design is focused on proper material distribution for high RPM, naturally aspirated applications. The beam features a tapered width and a tapered blade thickness, which allows robust big end bore geometry while reducing tensile load through reduced pin end mass. Housing bore stability is further enhanced by utilizing 7/16” fasteners for increased clamping force.
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Compstar connecting rods
Every Compstar connecting rod begins its life on the drawing boards of our Fostoria, Ohio engineering team. We don’t just buy off-the-shelf parts and put our name on them; we own the forging dies. This means the metallurgy and geometry are dictated by Callies’ standards—not by a third-party supplier. By utilizing a global supply chain for initial forging and performing the critical finish-work in-house, we deliver a product that is precision-finished and ready to race with consistency you can rely on.
Compstar rods are available in standard H-Beam and in our Compstar Xtreme.
When your build pushes past “street-performance” and enters the realm of heavy duty boost and high RPM racing, you need more than just a standard rod, you need the Compstar Xtreme. Designed for the engines that exceed the demands of the Compstar H beam, the Xtreme series takes the proven Compstar philosophy and reinforces it for high-stress environments with beefed-up geometry in critical areas.
For more information on Compstar click here.
Increased Stroker Clearance – The best bolt to block & rod to cam clearance in the industry for long stoke applications.
Bolt Spotface Gussets – Allow optimized bolt location without loss of strength or defomation of the big end bore.
100% Thread Engagement – Assures no bolt threads are left exposed in the area between the bolt thread and shank.
Specifically Designed, 260Ksi Ultra Bolts – All Ultra bolts are designed to fit each specific connecting rod. Rolled threads are employed to provide improved engagement for a more consistent clamping load. Callies provides and recommends the use of ARP Ultra torque lube. For a complete listing of recommended torque & stretch data, please visit our Rod Bolt Torque page.
*Pin ends are on center for all parts