Ford Big Block 429-460 Advertised Duration: 315/323 Duration @ .050": 283/291 Valve Lift w/1.73 Rockers: .779/.744 Lobe Separation Angle: 110 Intake Centerline: 106 Valve Lash: .022/.022 5200-7500. Big cubic inch 500+ motors, best with 13.5:1+, needs true race converter. |