How strong is my setup?

What heads, intake, carb and exhaust do you have? Assuming they have ARP or some aftermarket high strength rod bolts they are probably as good/or bad as any other SB rod unless you get in the $2k range. 6500rpm for a long stroke 416 is pushing it, I'd shift @ 5800-6K in 1st and 2nd and let it run out in 3rd. I have a 3.79 stroke and cross the finish line @ 6700 - works good.