SBF Shaft Rocker Arm Kit - 1.65/1.65 Ratio

The SBF Shaft Rocker Arm Kit - 1.65/1.65 Ratio is purpose-built for Small Block Ford engine builders and performance enthusiasts seeking to maximize valve lift and duration on their platform. This kit addresses a fundamental requirement in any serious SBF cylinder head upgrade: precise rocker arm geometry that translates camshaft motion into optimized valve actuation. Whether you're building a street engine, circle track racer, or high-horsepower street rod, the correct rocker arm ratio directly impacts power delivery, fuel efficiency, and engine responsiveness across the RPM band.

The 1.65/1.65 ratio configuration provides a mechanical advantage that lifts the intake and exhaust valves equally, making it ideal for applications where symmetrical valve events suit your cam timing and cylinder head characteristics. Shaft-style rocker arms distribute load across a full-length shaft rather than individual stud mounts, resulting in superior stability under high-RPM operation and reduced deflection during aggressive valve spring pressures. This design excels in forced-induction applications and high-lift cam scenarios where individual rocker arms can flex or deviate from their intended arc, compromising valve timing accuracy and risking valve-to-piston clearance issues. The kit's engineering ensures consistent ratio performance across all eight cylinders, eliminating the variances that can accumulate with stud-mounted alternatives.

This rocker arm kit is compatible with Small Block Ford heads featuring shaft-style mounting provisions and works across generations from the classic 289 through modern 302, 351W, and 393 stroker applications. Installation requires verification of your cylinder head's rocker arm boss design and pushrod length calculation—a critical step often overlooked by amateur builders that can result in improper valve lash and catastrophic engine damage. Experienced mechanics and dedicated hobbyists who are rebuilding or modifying their powerplants will appreciate the precision engineering that enables repeatable, reliable performance gains when properly sized for your specific cam profile and intended use.