well if ya got malhe's dont think ya deffo need new pistons tbh, im asuming ya got a stage 3 head and a decent cam ( cvh36 is a nice choice imo, then i did get it recomended by God )

just throw in rods and see what happens, remember at high rpm ya rods screw up so change em and see what happens

or aint rudey selling his old 1900 block, buy that, get decent rods and ya laughing