On a blower motor, i think and use alum rods. I got BME 5.850's in my 383" that put's the piston .025 down with a 9.000 deck, with a 1471 on alcohol, that's the only motor i have that will produce 1100 HP i think Alum rods absorb the impact a little softer therefore easier on the crank and bearings, but my other unblown S/BLK's have "H" beams or Lonatti promod rods.
JMO
Zip.