hey guys, quick question, i searched, but couldnt find any good info
i have a GT25 Turbo(journal, not ballbearing) off of a sr20DET motor and i was wondering should i be usuing an oil restrictor?
you didn’t search hard cause i found this on the garrett site in about 10 seconds and im not exagerating.
Does my turbo require an oil restrictor?
Oil requirements depend on the turbo’s bearing system type. Garrett has two types of bearing systems; traditional journal bearing; and ball bearing.
The journal bearing system in a turbo functions very similarly to the rod or crank bearings in an engine. These bearings require enough oil pressure to keep the components separated by a hydrodynamic film. If the oil pressure is too low, the metal components will come in contact causing premature wear and ultimately failure. If the oil pressure is too high, leakage may occur from the turbocharger seals. With that as background, an oil restrictor is generally not needed for a journal-bearing turbocharger except for those applications with oil-pressure-induced seal leakage. Remember to address all other potential causes of leakage first (e.g., inadequate/improper oil drain out of the turbocharger, excessive crankcase pressure, turbocharger past its useful service life, etc.) and use a restrictor as a last resort. Garrett distributors can tell you the recommended range of acceptable oil pressures for your particular turbo. Restrictor size will always depend on how much oil pressure your engine is generating-there is no single restrictor size suited for all engines.