The subject of H-beam versus I-beam connecting rods comes up every once in awhile, and it’s a fun topic for bench racing. But one thing I’ve noticed is that many enthusiasts have the mistaken impression that cylinder pressure loads, such as from superchargers or turbochargers, is what fails connecting rods. This tends to be reinforced by many connecting rod companies that rate connecting rods by horsepower. All connecting rods are designed to withstand incredibly high compressive loads. This is not what typically will cause a rod to fail. What tends to damage or fail a connecting rod is the change in direction, especially at bottom dead center (BDC) when the rod is subjected to tension and the rod bolts are strained to prevent the cap from pulling apart from the rod. This makes engine speed, rpm, the real connecting rod killer. Weight is another big factor, which is usually a bedfellow to strength. But the reality is that a lighter rod is most often better in an rpm application since the lighter rod presents less of a g-force load on the cap and rod bolts. This also makes the selection of a connecting rod bolt as important as the rod itself. Another point worth considering is that the big end of an H-beam rod tends to take up more space than an I-beam, which makes clearance an issue when it comes to stroker cranks. All this places the selection of I-beam versus H-beam far down on the list of important selection criteria.