A clean oil return is the difference between a turbo that lasts and one that doesn't — and this billet flange gives you the foundation to get it right.

Why Builders Choose This Flange

Precision Billet Construction

Machined from billet aluminium for exceptional strength and a leak-resistant sealing surface that holds up in the high-temperature environment of a working turbo oil drain circuit.

35mm Bolt Pattern for Small-Frame Turbos

The 35mm mounting pattern is designed specifically for small-frame turbochargers, making this a direct-fit upgrade over worn or undersized OEM-style drain flanges without the hassle of adapting ill-fitting generics.

10AN Port for Standard Drain Lines

The 10AN oil drain port works with widely available braided stainless and rubber AN hose, so you can route your turbo oil return line exactly where you need it — no additional fittings or reducers required in most setups.

Reliable Sealing Surface

The precision-machined face ensures a consistent, repeatable seal at the flange-to-turbo interface — critical for preventing oil weeping that can foul your exhaust and mask larger issues down the line.

Versatile Across Builds

Whether you're building a boosted street car, a track day weapon, or a diesel performance setup, this flange fits the job. Compatible with a wide range of small-frame performance turbos across gas and diesel applications.

Backed by BSI Inc.

Manufactured by Black Sheep Industries, this is a universal BSI Inc. component engineered for builders who refuse to cut corners on the details that matter.

Stop chasing oil leaks — fit it right the first time with the 35mm billet 10AN turbo drain flange for small-frame turbos from BSI Inc.

FAQ

What turbochargers is this flange designed for?

This flange uses a 35mm mounting pattern designed specifically for small-frame turbochargers.

What oil drain line size does this flange use?

It features a 10AN oil drain port that works with widely available braided stainless and rubber AN hose.

What material is the flange made from?

It is machined from billet aluminium for strength and a leak-resistant sealing surface.

Who manufactures this turbo drain flange?

This is a universal BSI Inc. component manufactured by Black Sheep Industries.