[MidOHasp]

2 bolt mains, stock block, probably right around 600 HP depending on revs. I don't think you can go too wrong w/ a stock block at 600HP, 6K RPM. That's easy. You can probably up one of those to a 7, maybe even both, but then you probably need to start thinking about girdling the mains.

Earlier you mentioned standard/stock parts, and I wouldn't say you can go that high. But with aftermarket rotating assembly, the block is tough and can hold up pretty well.

Reading what you're talking about - 6800RPM, NOS, etc...You'd be smart to go with the forged crank. Block will probably hold up fine. I'm not an engine builder, but I've talked to a lot of them, and a for a stock 2-bolt 351W, these guys say my 508HP is "pretty mild and pretty much bulletproof".

Ultimately, an extra grand in "solidification" can be a cheap insurance policy.