I'm a big fan of narrow lobe separation, and this graph shows why.

What is most interesting is that there is no power loss at 3000 RPM to gain 30Tq pretty much everywhere.

Cam 1: Stock LS3 
Lift: .551 in/ .525 ex
Duration @ .050: 204 in/211 ex
LSA: 117 
Idle vacuum: 20.3 in-Hg
PV Intake: .150+
PV Ex: .150+
Cranking Compression: 205 psi
Peak Power: 496 hp @ 5,800 rpm
Peak Torque: 491 lb-ft @ 4,700 rpm
Ave HP (3,000-6,500): 408.9 hp
Ave TQ (3,000-6,500): 452.4 lb-ft
Tq @ 4,000 RPM: 461 lb-ft

Cam 3: 231 Cam 
Lift: .617 in/ .624 ex
Duration @ .050: 231 in/239 ex
LSA: 113
Idle vacuum: 17.1 in-Hg
PV Intake: .041
PV Ex: .098
Cranking compression: 200 psi
Peak Power: 566 hp @ 6,400 rpm
Peak Torque: 517 lb-ft @ 5,200 rpm
Ave HP (3,000-6,500): 441.4 hp
Ave TQ (3,000-6,500): 485.4 lb-ft
Tq @ 4,000 RPM: 477 lb-ft

I copy and paste various things I find online as being useful information.

This was taken fromSuperChevy Magazine

Further, this show just how good LS heads are, if this where a Gen 1 350 peak Hp would have been much closer to 6000 RPM.

This duration increase show what one would expect, a loss at 3000 RPM to increase power at 6000 RPM. The peak power production is limited by port flow, so continuing to add duration will start to work against you.

Cam 4: 235 Cam 
Lift: .647in/.612ex
Duration @ .050: 235 in/244 ex
LSA: 111 degrees
Idle vacuum: 13.7 in-Hg
PV Intake: .003
PV Ex: .075
Peak Power: 573 hp @ 6,400 rpm
Peak Torque: 526 lb-ft @ 5,200 rpm
Ave HP (3,000-6,500): 449.4 hp
Ave TQ (3,000-6,500): 494.5 lb-ft
Tq @ 4,000 RPM: 484 lb-ft

Cam 2: 224 Cam 
Lift: .624 in/ .590 ex
Duration @ .050: 224 in/232 ex
LSA: 113
Idle vacuum: 20.3 in-Hg
PV Intake: .117
PV Ex: .150
Cranking Compression: 205 psi
Peak Power: 547 hp @ 6,300 rpm
Peak Torque: 514 lb-ft @ 5,100 rpm
Ave HP (3,000-6,500): 37.6 hp
Ave TQ (3,000-6,500): 82.6 lb-ft
Tq @ 4,000 RPM: 480 lb-ft