A non-twist steel forging is supposed to be superior to a billet steel crank. If I remeber correctly the grain structure in the billet is still distorted when the billet was forged? Anywhosit, Unless your going for a max effort motor then the billet piece is overkill. A nodular iron or cast steel crank can tolerate in the neighborhood of 600 hp and about 6000-7000 rpm reliably if it is prepped right. A forged crank even more. The money you spend on a billet piece could go somewhere else. For $h1ts and giggles you could take that same money and have the rods, block, and crank cryogenically treated and probaly still have some bucks left over to put a thermal barrier coating on the pistons and heads, then coat the skirts themselves (if you want to spend a few bucks and increase the power and strength). Or whatever floats your boat. I think the only real advantage a billet crank has over a forged unit is that it can be cut to fit any sort of oddball combination without setting up some dedicated dies. Or even better put it toward an aluminum block!
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