440 Camshaft recommendations for up to 6-6,500 rpm?

Ricks70Duster340 said
The factory rating was quite underrated. The stock 440 HP made closer to 425, and the 6 pack 450. Any engine can benefit from breathing improvements!

The evidence I've seen points to the 4v motor making close to the rated hp. The 6 Pack maaaybe? slightly underrated. 340 and Hemi probably underrated. 318 at 230 hp is overrated.