The RB26DETT engine is often plagued with oil lubrication issues during circuit and drag racing events which are the main causes of most RB26 engine failures. This problem causes the main bearings to abnormally wear out from the lack of oil pressure. The stock pump is not capable of supplying the adequate amount of oil to maintain the right oil pressures at extreme engine speeds that the high powered monster RB26 performance engines require. Another weak point is that the stock pumps gear is made from weak sintered metal and this often breaks when going for bigger power and higher engine speeds and when this little piece gives out can cause an instant loss of your engine. The TOMEI RB26 oil pump has a larger pump gear made of high strength materials to supply a larger flow rate to the engine and it has an external oil pressure adjuster as well.