I think Rickster is on the right track, but I think he needs to calculate the moments of inertia for Iyy in addition to Ixx that he did. I had this discussion with a friend in Tampa about which plane you think has the highest stresses/loads. If the piston is not centered on the rod, then maybe the H-beam looks more attractive? I never did the calculations for a rod, but I ran a similar analysis on a rocker arm design since I think they put the slot in the top (remnants of the Shivy ball stud arrangement) instead of more like the Chrysler forged rocker arms. The top slot did a lot better than I thought it would and actually was slightly better than the I-beam design.
