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

The thing about an RB engine is you don't need to spin it to the moon to make good power. I prefer to keep the R's at 6K or below. With the longer stroke, just think how fast that piston is moving & the stress. Just my opinion, of course!
I know, I'm just replying to the OP . I don't believe he can make power at 6000-6500 with a ported 915. BTDT