The Simply Sports Cars oil pump gear set for the 2ZZ-GE engine is precision cut from 4340 High tensile steel using a high precision process called EDM (electron Discharge Machining) wire cutting. This gives a smoother surface finish but is also the most accurate method of machining parts which demand highly accurate tolerances. The OEM gears are sintered which is a good method for producing accurate parts however it leaves them low strength. An engine over rev can be all it takes to cause these gears to fail.
Learn more about the general benefits of oil management in the video below