anything around 490s lift int and exhaust. Here are a few choices.
I would go with steeda #19. Most people like it
1.Stock 5.0 E8ZE-6250-CA, Valve Lift Intake w/1.6 rockers-.444,
Valve Lift Exhaust w/1.6 rockers-.444, Duration Intake (at .050)-204, Duration Exhaust (at .050)-204, Lobe Center-116, Emissions Legal-Yes
3.Lunati 50017, Valve Lift Intake w/1.6 rockers-.500, Valve Lift Exhaust w/1.6 rockers-.510, Duration Intake (at .050)-218, Duration Exhaust (at .050)-226, Lobe Center-112, Emissions Legal-No
4.B303, Valve Lift Intake w/1.6 rockers-.480, Valve Lift Exhaust w/1.6 rockers-.480, Duration Intake (at .050)-224, Duration Exhaust (at .050)-224, Lobe Center-112, Emission Legal-No
5.Crane 2040, Valve Lift Intake w/1.6 rockers-.498, Valve Lift Exhaust w/1.6 rockers-.498, Duration Intake (at .050)-220, Duration Exhaust (at .050)-220, Lobe Center-110, Emissions Legal-Yes
6.Crane 2030, Valve Lift Intake w/1.6 rockers-.533, Valve Lift Exhaust w/1.6 rockers-.544, Duration Intake (at .050)-216, Duration Exhaust (at .050)-220, Lobe Center-112, Emission Legal-Yes
7.Crower 15511, Valve Lift Intake w/1.6 rockers-.468, Valve Lift Exhaust w/1.6 rockers-.486, Duration Intake (at .050)-218, Duration Exhaust (at .050)-224, Lobe Center-114, Emission Legal-Yes
8.Crane 2031, Valve Lift Intake w/1.7 rockers-.513, Valve Lift Exhaust w/1.7 rockers-.529, Duration Intake (at .050)-214, Duration Exhaust (at .050)-220, Lobe Center-112, Emissions Legal-Yes
9.Steeda #19, Valve Lift Intake w/1.6 rockers-.480, Valve Lift Exhaust w/1.6 rockers-.480, Duration Intake (at .050)-220, Duration Exhaust (at .050) w/1.6 rockers-226, Lobe Center-115, Emission Legal-Yes
10.E303, Valve Lift Intake w/1.6 rockers-.498, Valve Lift Exhaust w/1.6 rockers-.498, Duration Intake (at .050)-220, Duration Exhaust (at .050) w/1.6 rockers-220, Lobe Center-110, Emissions Legal-Yes