Roller Rockers for 351C,351M,400,302 BOSS,429,460,429CJ,429SCJ Cylinder Heads Application: 351C/351M/400 302 BOSS/429/460, 429 CJ/SCJ and Ford Racing high port aluminum cylinder heads. Ratio Mounting: 1.73:1 Bolt On. Valve Type: Canted. Notes: For canted valve cylinder heads. Requires 7/16" stud, push rod guide plates, hardened push rods. Some cast iron cylinder heads require pedestal machining