In racing main bearings, the groove’s shape and size perform a vital role. The groove should be wide enough to allow sufficient oil flow, but narrow enough to maximize the working surface.
In today’s race engines, contrary to popular belief, there is significant load on the upper main bearing shells. The extra load is a product of the inertia forces generated by high RPM. The extra force demands higher load capacity.
In response, King Racing’s TechLab developed U-Groove – a unique 90-degree oil groove shape. U-Groove increases bearing load capacity by expanding the surface area, while keeping oil flow capacity intact.