Best type of turbo flange gasket?

[Pupp]

Bit dull I know, but any views on what's best for longevity, a single leaf steel gasket with a crush ridge around the aperture or a multi-leave composite flat type?

[mighty kitten]

Best type I've found is none , if both surfaces are good I use hmp grease as a gasket and don't fully tighten the bolts until a few miles of fairly gentle driving with some boost to get it hot enough to carbonise the grease . Torque the nuts up and have yet to have an issue .

[stevieturbo]

As above. If both flanges are flat, no gasket is needed. At a push maybe some high temp copper silicon.

And if the flanges are not flat, make them flat.

But if you absolutely insist on using a gasket of some sort, then yes a plain steel shim, with the raised bump

[Pupp]

Thanks gents, happy to try without