Engine RPM?

If they're reconditioned, they SHOULD have new rod bolts. Your bottom end should be good to 6500 rpm but with that cam, I see no reason to spin it that high. Your valves will most likley float and your cam be way out of it's powerband by 6000 rpm anyway. I'd start shifting at 5500 and move up in 100rpm increments until it slows down or you feel the valves start to float.