Carrillo S9855 CARR Multiphase Connecting Rod Bolt Replacement Fastener

The Carrillo S9855 is a CARR-series Multiphase replacement connecting rod bolt from CP-Carrillo — one of the most respected names in performance engine fasteners. Identifiable by its "S"-prefixed serial number, this bolt is a direct replacement CARR fastener engineered for use with compatible CP-Carrillo connecting rods in high-performance and motorsport engine builds.

Key Features:

• Multiphase construction — rated at 285 KSI ultimate tensile strength, significantly stronger than H11 tool steel WMC alternatives
• Asymmetrical thread design — each thread features a slightly different profile than the previous, distributing thread engagement evenly to increase clamp load and improve fatigue life
• Aircraft-standard fastener — precision manufactured to exacting dimensional tolerances for consistent stretch and preload
• Unlimited torque cycle rating — CARR bolts can be reused indefinitely when proper stretch installation procedures are followed and the bolt has not been overstretched or overheated
• Stretch installation method recommended — CP-Carrillo specifies stretch to 80% of known yield load for optimal preload; torque method is secondary due to variables that affect true preload
• Molybdenum-based assembly lube compatible — lubrication under the bolt head and on threads is required for proper clamp load and torque consistency

CP-Carrillo CARR-series fasteners are the standard choice in professional engine building where high RPM, forced induction, or endurance racing demands maximum clamping reliability. Always refer to the torque and stretch specifications provided with your specific connecting rod assembly.