Stop fighting with undersized, poorly machined drain flanges. This is the clean, high-flow solution your turbo build deserves.

Features & Benefits

Precision CNC-Machined Billet Construction

Machined from billet aluminium for a level of accuracy and surface finish that cast or overseas knock-off flanges simply can't match. Every port and bolt hole is held to tight tolerances so you get a proper seal and a clean install the first time.

50mm (1.97") Bolt Centre for Mid-Frame Turbos

Machined to the 50mm bolt centre used by mid-frame turbochargers, including both journal-bearing and ball-bearing units. Bolt centre is measured from the centre of one drain pad bolt hole to the centre of the other — 1.97 inches on mid frame. No adapting, no guessing, no shimming.

100mm (3.94") Drain Length

The 100mm figure is the length of the drain — how far the drain body stands off the flange face before your hose connects. This is the longest of the three lengths we offer, giving you the reach to get your hose connection out past a manifold, frame rail, or block accessory. Also available in 35mm (1.38") and 65mm (2.56") for tighter installs.

High-Flow 10AN Oil Return Port

The 10AN port keeps oil moving freely back to the sump, reducing the risk of oil pooling in the centre housing, one of the most common causes of turbo seal failure and premature bearing wear. Pair it with a quality 10AN drain line and you're set for serious street or track duty.

Made by BSI Inc.

Engineered and produced by Black Sheep Industries, this flange is built to a standard you'd expect from a dedicated turbo components manufacturer, not a catalogue importer. Whether you're ordering from Calgary or California, you're getting the same quality part with the same commitment behind it.

Every turbo build lives or dies on the details. Start your oil return system with a flange that's actually worth trusting.

Not sure which drain you need? See the turbo oil drain guide for bolt centre measurement, length selection, and full sizing charts in metric and US standard.

FAQ

What turbochargers is this drain flange designed for?

It is machined for mid-frame turbochargers, which use a 50mm (1.97") bolt centre, including journal-bearing and ball-bearing units.

What does the 100mm refer to?

100mm (3.94") is the length of the drain, meaning how far the drain body stands off the flange face. It is the longest option and is chosen when you need reach to clear obstructions around the drain pad. It is not the bolt centre or the port size.

What is bolt centre?

Bolt centre is the distance from the centre of one bolt hole to the centre of the other on your turbo's oil drain pad. It identifies the frame class: 38mm (1.50") small frame, 50mm (1.97") mid frame, 50.8mm (2.00") large frame.

What size is the oil return port?

This flange uses a high-flow 10AN oil return port to help move oil freely back to the sump.

What material is the flange made from?

It is precision CNC-machined from billet aluminium for accurate port and bolt-hole placement and a clean surface finish.

Who manufactures this turbo drain flange?

It is engineered and produced by BSI Inc., also known as Black Sheep Industries.