I have read the warnings before on Stainless, and it does seem that all stainless might not be to the same spec. I do not profess to know the tensile strengths of marine grade (316 ?) or any others, but on sail boats there are stainless fittings and fixings subjected to considerable loads..?

Also if I might add there were rather a lot of stainless fixings used around my +8 when it was rebuilt some 20 years ago... as to their grade, I have no idea. My +8`s exhaust manifolds are held in place by stainless set screws and having read on the www of numerous tales of SS seizing into alloy heads, I checked a few of my manifold set screws in the recent past, and they came undone without issue having been holding the manifold for more than 20 years.

Having typed the above I have also seen many stainless fixings seized solid into alloy when exposed to the weather in non-automotive situations.


I am also aware of the watercooled Porsche exhaust fixing issues and the various methods or resolving them.

I kinda like the idea of studs with nuts. In times past the nuts were brass thus unlikely to seize... With nuts and studs you may have a better chance of getting a nut off without sheerng a stud whereas with set screws, I guess sheering is ever a possibility, more so if they are made of the same metal Porsche seem to prefer..!