Straight Flow Exhaust Flanges & Gaskets

Straight Flow’s flanges are mostly stainless (‘inox’) turbo outlet flanges: the plate a downpipe is welded to where it bolts to the turbocharger, plus a flange for a diesel particulate filter. Each is named by the engine code it suits, so the engine, not the model, is what to check, and some come as separate left and right flanges. Several turbo flanges also give the outlet size, 76 mm or 90 mm, which sets the diameter of the downpipe.

The rest are flange pipe connectors in 409 stainless steel for 45 mm to 65 mm pipe, a simple bolted joint for a universal system.

A turbo flange is a fabrication part. Tack it to the pipe with the flange bolted in place on the engine, so that the downpipe lines up before it is fully welded. Check that the gasket face stays flat after welding. Order a new gasket and fixings for the turbo at the same time.

These flanges suit a downpipe or turbo-back system built to your own layout, and they go with the same brand’s stainless tube and bends.