I've been running two bolt main blocks as long as I've been running small block Mopars. My engines have ranged from a basic stock motor to the 416 stroker motor I'm running now. My 416 dynoed 623 hp, 511 lb/ft torque @ 6400 RPM. I've had no problems, other than one thin cylinder wall due to .060 over bore & that was due to not having the block sonic tested. But being as my current set up is race only, I did a full fill of HardBlok just for stabilization.
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