^^^^^Have you seen what else they have run on the stock bottom end. There is a recent post by rips in the rb30 section. A built standard bottom end will handle that with some mods.
quote from rips
I can also vouch for stock RB30 cranks to 9000rpm 1000+hp, and stock RB30, pistons and rods to 8000rpm and over 500rwkw in a track car without problems, although I usually tell my customers 7200rpm, 1.5 bar 400rwkw.
If have money to burn.....