First, yes you would split the block, maybe not right away... but you will do it. It's only a matter of time...
Now that being said...
Do you really know what "only 500hp" is like to try and drive?
I've got a little tiny 306... makes 310whp.
Runs 13.5 at 106, with a corner carving
suspension and 3.08 rear gears. (street tires, full stereo, etc...)
I can be running around in town at 35-40, stuff it in 2nd and jump on it and it'll light the tires to 55 when I shift to 3rd...
I mean with 500whp you're talking about fogging the tires at 80mph on dry pavement...
is that really what you want to drive all the time? ...really?
Yeah it's bitchin at the dyno shootout or for braggin at the local starbucks... but do ya reallllyyyy want that much pain and heartache, just lying in wait for your first lack of discression?
( ...really ? )
Get yourself about a 400-425bhp 347 with a tremec behind it... and slide it in that bad boy, with a set of 3.55's or 3.73's and you'll have ALL KINDS of s**ts and giggles, truuuussstt me.