I think LS2 is the way to go.
Figures from the Hot Rod test
LS2 Cam
Peak Power 403 at 6,100 rpm
Peak Torque 399 at 4,900 rpm
Average HP 305
Average TQ 370
HP/TQ Gains (Over LM7 cam) at 2,500 -18 lb-ft
3,500 0
4,500 0
5,500 +46 lb-ft (48 hp)
6,200 +67 lb-ft (78 hp)
LS6 Cam
Peak power 376 at 5,900 rpm
Peak torque 389 at 4,500 rpm
Average HP 296
Average TQ 362
HP/TQ Gains (Over LM7 cam) at 2,500 -8 lb-ft
3,500 0
4,500 0
5,500 +23 lb-ft (24 hp)
6,500 +32 lb-ft (40 hp
P.