I ran that cam in my 500" and it didn't peek until 6800, shifted at 7000, now I've got the smaller 23-633-5 it peeks at 6400. Your cam is to big if your only going to 6200.

As a note mine has 915 heads 2.18/1.81 25.5 cr and made 645 hp and 620 tq on E-85. Is 40 hp worth the cost of the heads? My junk has been together since 91, if I was starting over I would go with them, but I have a lot of parts to use up.