Camchest - Race Series® - Reaper 521 - Oil Cooled - M8Billet 7075 aluminum oil pump, which is 50% harder and stronger than the factory pump, holding tighter tolerances under temperature Short travel hydraulic lifters have 0. 115" of total travel and will increase rpm by decreasing valve float and valve train harmonics while maintaining a quiet engine Deeper scavenge kidney ports over the HP+ series for even more scavenge flow volume 30% more pressure gear volume over stock for M Eight Twin Cooled motors