Chevrolet BB Mark IV 396-502 1965-1996 Advertised Duration: 309/319 Duration @ .050": 277/287 Valve Lift w/1.70 Rockers: .737/.737 Lobe Separation Angle: 108 Intake Centerline: 104 4400-8000. Good upper RPM cam in big cubic inch engine with 13.0:1+ CR.
Chevrolet BB Mark IV 396-502 1965-1996 Advertised Duration: 309/319 Duration @ .050": 277/287 Valve Lift w/1.70 Rockers: .737/.737 Lobe Separation Angle: 110 Intake Centerline: 106 4200-7800. Works great in 496+ CID with high stall. Will work with NOS.
Chevrolet BB Mark IV 396-502 1965-1996 Advertised Duration: 309/319 Duration @ .050": 277/287 Valve Lift w/1.70 Rockers: .737/.737 Lobe Separation Angle: 112 Intake Centerline: 108 4000-7600. Great super class cam. Best in 540+ cubic inch. Easy on valve train.
Chevrolet BB Mark IV 396-502 1965-1996 Advertised Duration: 313/319 Duration @ .050": 279/287 Valve Lift w/1.70 Rockers: .771/.737 Lobe Separation Angle: 110 Intake Centerline: 106 4500-8000. Works great in 496+ CID with high stall. Will work with NOS.
Chevrolet BB Mark IV 396-502 1965-1996 Advertised Duration: 315/319 Duration @ .050": 283/287 Valve Lift w/1.70 Rockers: .765/.737 Lobe Separation Angle: 114 Intake Centerline: 110 4800-8000. Competition only in 500+ CID, needs high CR, stall & gears. Good with NOS.