AN 4 T3/T4 Turbo Oil Feed Adapter Flange For Ball Bearing Turbos

• CNC machined from T6061 billet aluminum
• AN 4 inlet fitting for use with braided AN 4 oil feed line
• Features .042-inch oil restrictor machined into oil feed port
• Restrictor can be drilled out for use with journal bearing turbos
• Includes base gasket and Allen head cap screw mounting hardware

Ensure Your Ball Bearing Turbo Is Fed the Proper Oil Pressure

When planning your turbo build it is critical to ensure your turbo is fed the proper oil pressure for a long life of lubrication and cooling. Ball bearing turbos use a bearing cartridge in the bearing housing that supports the central shaft that both the turbine wheel and the compressor wheel are mounted to. These bearings must be fed oil from the engine via a fitting on the engine itself that is carried to the turbo’s center housing via a -4 AN braided oil line. This path feeds engine oil to the bearings at whatever pressure your engine’s oil pump is capable of. So, if you are running a high pressure pump you may be providing too much oil to your turbo’s bearings, which can cause oil consumption and leakage from the turbo, not to mention slowing the boost response of the turbo. The fix? An inline turbo restrictor that limits the oil pressure to your turbo.

Adding an oil restrictor to your turbo’s feed line is essential for a ball bearing turbo, but why introduce yet another fitting and potential failure or leak point in your oiling system? Instead, replace your standard turbo oil inlet fitting with our direct fit bolt on adapter that is machined for a standard -4 AN feed line and incorporates the necessary turbo oil pressure restrictor fitting for your turbo’s oil feed? No need to cobble together adapters from the plumbing aisle at your hardware store or try to use an old nitrous jet as a turbo oil restrictor for the oil supply. Simply bolt on our turbo oil restrictor fitting adapter to your turbo and run your AN line. Our integrated .042-inch turbo oil pressure restrictor will bring your engine’s oil pressure into an acceptable range for your ball bearing turbo build without a big stack up of adapters that can crack from vibration or come loose and leak.

Made from T6061 billet aluminum and CNC machined for precision fit and oil flow, our adapter comes ready to install with a high temperature base gasket and Allen head cap screws to secure the inlet adapter to your T3/T4 turbo oil inlet port. Don’t worry if you’re using a journal bearing turbo in your build, you can still incorporate our oil feed turbo fittings in your plans. All you need to do is drill the restrictor port out to approximately .25-inch to match the ID of your -4 AN line and your journal bearing turbo will see plenty of oil. Don’t forget to incorporate a high flow oil drain of at least -10 AN from your turbo back to the engine’s crankcase to further reduce oil pressure issues that can cause low boost, oil leaks, smoking, and other issues within your turbo system. Using the proper inlet and outlet turbo fittings will ensure a long life for your turbo.