I think 600ish with a good block, some oiling mods and the aforementioned girdle is not a problem. I've been beating on mine for 4 seasons. Long drives with wifey, all the cruises, and all the local yocals who wanna try me.
I have a SCAT forged crank and H beam rods. I'm afraid of no man nor beast.................except spiders and Eagle cranks. Just my own useless opinion.