Restored faith in my z6 crank purchaseThe deeper V of the bearings creates a channel that supposedly carries the oil around to the single oil hole just as effectively as the 2 hole earlier design, allowing rod journal oiling to remain constant no matter the position of the hole in the crank relative to the hole in the block. higher power levels, however, deform the main bearing and allow oil to escape dropping oil pressure on the rod journal as the hole on the crank moves away from the hole in the block. With 2 holes picking up oil to push to the rod journal the Z6 crank handles higher compression/boost better as it can maintain oil pressure at the rod journal throughout both compression and power strokes. Look at wear patterns on y8 cranks vs z6 cranks and the results are quite obvious. The y8 will be ovaled from top to bottom when crank is mid stroke, while the z6 wears near even circle.