Oil Feed Requirements

For all Bullseye Turbocharger models (SB, BMW, TCT, and NLX):

• We recommend all oil feed lines be constructed with a -4 AN braided steel Teflon line.

• Do not use a “T” or “Y” splitter on oil feed lines for twin turbo applications.

• Each turbo must have its own dedicated -4 AN braided steel Teflon line directly from the oil filter housing.

Journal Bearing Turbochargers

• Do not use an oil feed restrictor unless:

  • Oil pressure exceeds 80 PSI, and/or

  • There is an oil control issue (e.g., smoking, oil dripping from the exhaust).

• If a restrictor is required, use one no smaller than 0.080”, unless otherwise specified.

NLX Ball Bearing Turbochargers

• All NLX turbochargers produced on or after 01/19/2019 include a built-in oil feed restrictor.

• In some applications, an additional restrictor may still be required—particularly with:

  • High oil pressure

  • Thick oil

  • Poor crankcase ventilation

  • Inefficient oil drain systems

• For guidance on the correct restrictor size, call (231) 787-5209 before proceeding.

Billet Center Sections

• As of 01/19/2019, all billet center sections use -4 ORB oil feed fittings.

• Only cast iron center sections use ¼” or ⅛” pipe thread, with the exception of 2 specific models.

Turbocharger Oil Feed Thread & Bolt Sizes

• All BEP turbochargers with two threaded holes on the oil inlet side (small end):

  • Use a bolt-on oil feed flange.

  • Flange mounting requires M8 x 1.25 bolts.

• Turbo sizes 256 (56mm) and 259 (59mm), with a 4-inch OD compressor inlet, use ¼ BPT (British Pipe Thread).