ULTRA Pro Magnumâ„¢ Roller Rocker Arms. The Ultra Pro Magnumâ„¢ Roller Rocker Arms not only live up to the lofty standards of the original Pro Magnumâ„¢ Rockers, but they also take Stud mount Rocker performance, stability and value to a whole new level. The modern arched, web-like design delivers increased strength and rigidity while still reducing the moment of inertia and optimizing the dynamic balance. Applications: Chevrolet Small Block 265-400 c.i.d. V8 3/8" Studs / 1.52:1 Ratio.Investment cast 8650 chromemoly body and arched, weblike design deliver increased strength and rigidity while reducing M.O.I.Unique black oxide exterior finish helps prevent corrosion, thus increasing durabilityIncreased retainer and valve spring clearances allow use of large diameter springs, retainers and +.050" locks with o clearance or fitment issuesFeature Oversized trunnions, precision-sorted needle bearings and hardened Roller tipswithstand valve spring pressures up to 850 lbs.Also Available in A Rocker/Pushrod Kit
