i have a buddy of mine that has a 509 gm 2 bolt block...callies 4340 crank...
i would say he is making about 800hp on motor and sprays it 250hp..he has had no problems and is going on his 3rd season with motor.....he did hurt a head gasket last year but totally unrelated to the mains..
there are some theory's going around now about 2 bolt mains being stronger..i am not taking either side...but do know my buddy runs 5.50's in a 2900 lb car with a 2 bolt block.....
would i purcahse a 2 bolt block over a billet steel splayed 4 bolt main....NO i would not !!!..but if i had the 2 bolt and could use it for little money...why heck ya...jump in there and do it...my opinion only.
Remember your question, "how much HP could a 2 Bolt take?"
Solid Proof is out there every day 800 to 850 hp and holding up for a good while...
Brian
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Bjuice..
"I'M YOUR HUCKLEBERRY ! "