The latest development in Rocker arm Technology from COMP Cams are Ultra Pro Magnumâ„¢ XD Rocker Arms built for 1/2" Studs to increase valve train stiffness and stability. Designed to be used in conjunction with the COMP Cams Hi-Tech 1/2" Rocker Stud Kit, the latest versions of COMP Cams Ultra Pro Magnum XD are built to utilize 1/2" Studs to stabilize SBC valve trains. Ultra Pro Magnumâ„¢ XD Rockers are built to outlast and outperform in accuracy and strength, while maintaining all the benefits of the Ultra Pro Magnumâ„¢ version. The XD Rockers are engineered from durable 8650 Steel and include a machined billet Pushrod seat insert for a super-accurate ratio. The Rockers also boast precision-sorted needle bearings and hardened Roller tips. And since they now feature the added benefit of accepting 1/2" Studs, they are a great choice for anyone looking for more stiffness with Stud mount Rockers. These new Ultra Pro Magnumâ„¢ XD Rocker Arms will provide the ultimate in valve train stability for maximum valve motion both at the track and on the street. 1/2" Studs provide a stiffer valve train to achieve maximum valve motion in SBC engines Deliver increased strength and rigidity while reducing the moment of inertia and optimizing dynamic balance Ultra Pro Magnumâ„¢ XD Rockers feature a machined billet Pushrod seat insert for a super-accurate ratio

Machined from 8650 steel with a billet pushrod seat insert, these Ultra Pro Magnum XD rockers can handle up to 1,000 lbs of spring pressure. These 1810 rockers feature a 1.5 ratio for use with 1/2" stud Chevrolet 265-400 Small Block.