SBM Xtreme Hyd. Roller Cam XR258R-12

The SBM Xtreme Hyd. Roller Cam XR258R-12 by COMP CAMS is a high-performance hydraulic roller camshaft engineered for street and strip applications where aggressive valve lift and duration demand reliability without traditional solid roller complexity. This cam is built for enthusiasts and professional builders who need substantial power gains while maintaining the low-maintenance, self-adjusting characteristics of hydraulic roller technology. Whether you're upgrading a small-block engine for weekend track duty or building a street cruiser that demands serious top-end horsepower, the XR258R-12 delivers the aggressive profile needed to unlock cylinder head potential.

Built with COMP CAMS' proven metallurgy and precision grinding, this hydraulic roller cam features a ground profile optimized for maximum valve velocity and increased overlap, critical for scavenging exhaust gases and maximizing volumetric efficiency at high RPM. The roller design reduces friction and wear on lifters and pushrods compared to flat-tappet alternatives, allowing this extreme profile to operate reliably in street engines without the expense and complexity of solid roller conversion. The XR258R-12 designation indicates a purpose-built grind with extended duration and lift values that require matching valve springs, rocker geometry validation, and careful tuning—this is not a bolt-and-forget upgrade but rather a precision component for informed builders.

Installation demands verification of lifter compatibility, pushrod length, and rocker arm geometry to ensure proper valve control throughout the RPM range. Small-block engine builders—particularly those working with Chevrolet, Ford, or similar displacement platforms—will find this cam pairs well with aftermarket cylinder heads, intake manifolds, and tuned exhaust systems that can exploit the aggressive valve timing. Dyno testing and professional installation are strongly recommended; this specification represents serious performance intent and requires corresponding supporting modifications for safe, reliable operation. With proper setup, the XR258R-12 transforms a stock or mildly modified engine into a formidable power plant.