• Ford V8 Boss 302, 351C, 429-460 - 7/16" Stud - 1.7 Ratio
• Investment cast 8650 chromemoly body and arched, web-like design deliver increased strength and rigidity while still reducing the moment of inertia. Unique black oxide exterior finish helps prevent corrosion and increases durability.
• Optimized retainer and valve spring clearances allow for use of most diameter springs, retainers and +.050" locks without clearance or fitment issues.
• Feature oversized trunnions, precision-sorted needle bearings and hardened roller tips.
• For use with up to 850 lbs of open spring pressure.

Ultra Pro Magnum™ Roller Rocker Arms not only live up to the lofty standards of the original Pro Magnums™, but they also take stud mount rocker performance, stability and value to a whole new level. The 8650 chromemoly material and arched, web-like design deliver increased strength and rigidity while still reducing the moment of inertia and optimizing the dynamic balance. A unique black oxide exterior finish helps prevent corrosion and increases durability. Featuring oversized trunnions, precision-sorted needle bearings and hardened roller tips for the ultimate in performance and dependability. Optimized retainer and valve spring clearances allow for use of most diameter springs, retainers and +.050" locks without clearance or fitment issues.