19210729 Aluminum Roller Rocker Arm 1.6:1 Ratio, Replaces 12370839

These small block 1.6:1 ratio aluminum rockers are similar to the rockers used in the 1996 Corvette LT4 engine, except the trunnions have been machined for early model 3/8" rocker studs.<br> These kits of 16 rockers include nuts and instruction sheets.

They are self-aligning style rockers with washers between the rollers and the rocker body for improved wear characteristics. By reducing the length of the rocker stud slots, it improves the stiffness by 30% over comparable aftermarket designs.

These rockers will accommodate up to .575" valve lift.
One of the main advantages of these rockers is about 2 lbs-ft in rotation torque, which provides a quieter idle. 

Technical Notes: When using a high lift camshaft, be sure to check for valve spring coil bind, retainer to seal clearance, and piston to valve clearance. When using valve covers with drippers, it may be necessary to remove them for proper rocker arm clearance. When using on cast iron head check for adequate pushrod clearance.

Cannot be used on ZZ3 engines with orange valve springs