I would use a Scat 4" crank, 360 mains if your sticking with the stock block. Your not saving a ton with chevy rods and pins IMO. What kind of cam (FT or roller or hyd roller)are you planning? RPM? Any rules? I love building road race and circle track engines...they are a nice challenge and fun to watch go around the track. Still waiting for my book Andy LOL!!