Properly balanced and oiled cast crank will take all you can give it on a street strip type motor. Six-seven thousand rpm in short bursts is common. I have more than several "Saturday Night Special" engines out that are cast crank and winners..
Hyper eutectic pistons also. I have left turners that get two-three seasons on them.. Secret is proper ring gap and wall clearance..
Only cast rods I deal with are Buick-Pontiac. Low rev motors..
SBC or BBC rods work well with new rod bolts and mag/resize. Unless you get int real big hp numbers. Then I go for aftermkt stuff..