В факе гаррета все написано:
Ball-bearing turbochargers can benefit from the addition of an oil restrictor, as most engines deliver more pressure than a ball bearing turbo requires. The benefit is seen in improved boost response due to less windage of oil in the bearing. In addition, lower oil flow further reduces the risk of oil leakage compared to journal-bearing turbochargers. Oil pressure entering a ball-bearing turbocharger needs to be between 40 psi and 45 psi at the maximum engine operating speed. For many common passenger vehicle engines, this generally translates into a restrictor with a minimum of 0.040" diameter orifice upstream of the oil inlet on the turbocharger center section. Again, it is imperative that the restrictor be sized according to the oil pressure characteristics of the engine to which the turbo is attached. Always verify that the appropriate oil pressure is reaching the turbo.
The use of an oil restrictor can (but not always) help ensure that you have the proper oil flow/pressure entering the turbocharger, as well as extract the maximum performance.
Ристриктор можно просто сделать. берешь болт M4. Отрезаешь от него 4мм кусочек, сверлишь в нем 1 мм или меньше сверлом дыру, с торца под отвертку насечку и вкручиваешь в тот ристриктор, который штатно у 28RS на входе (в нем как раз M4).
А банжоболт болт думаю можно ниссановский 16432-69F1A с SR20DET. если GT2560-466541-4 туда директ фит, то по идее он должен подходить. Для проверки себе заказал, правда идет три недели и будет только в апреле. А вытачивать 7/16 на 24витка плашку хрен найдешь.
на 20 есть на 24 нет.
