Oil control is a big deal in these motors, and we're not just talking about oil pressure. Because race teams depend so much on aero, they tape up as much of the grille as possible, so controlling the oil temperature is also important. One thing engine builders have found is that opening up the connecting rod side clearance can help keep the oil temps cooler without harming the bearings. But the connecting rod position must still be controlled, so they do it by bringing in the pin towers so that there are only a few thousandths of an inch between the small end of the rod and the cheeks of the piston's pin towers. This not only helps guide the connecting rod, but it also shortens the piston pin which can lower the overall reciprocating weight.