[HWYSTR455]

If you have a rotating assembly, yeah, would probably have the assembly prepped and balanced. But contrary to what many say, OE cranks are a crap-shoot, have seen many with stress cracks that 'reveal' themselves under use. Or during magnaflux.

If the crank doesn't check out, you may have to re-evaluate your direction forward, guess you can wait 'til that happens before you decide, but you will still owe for the machine work, etc. New cranks are like $325, which still need machine work.

Remember, even new rods need to be at least checked, if not sized.

You probably should balance the assembly too.

That stuff adds up. Rotating assemblies are usually ready to install, with all machine work already done. Maybe price it out, see what the difference is, it might help with the process.

Is the block prepped? Bore & hone for your pistons? Align bore checked? Decks checked/prepped?

Nothing wrong with a 400, and yes, gear it properly and it will be nice, but in general, by gearing it 'right', you will probably want an overdrive. You generally don't have to gear a longer stroke engine as much, and can be made move livable with slightly more 'highway' gears. And still perform well.

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