I just looked back through the book and you're right.
I think Harry (my machinist) just didn't want to remove too much metal so he wouldn't increase the chamber size and lower the compression too much. He told me of times where customers wanted oversized valves (larger than his recommendation) and the car actually slowed down (drag racing). But maybe I'll just take the book up to his shop and let him look through it some.
Thanks,
Wayne
