Nitrous on a 318.....how much will it take

There are some oddball things we find out that no one hardly even believes it's possible.
Way back when these cars were fairly new (as in the late 60's early 70's) my Dad told me you couldn't blow up a stock 318 if it was in decent condition in the first place.
He put his foot to the floor in park, and revved the piss out of that 318 until the valves floated and wouldn't scream any faster and held it there for 5 or so seconds.
He also taught me about valve float that day.:D