Mike Spera wrote:



I always wondered why we use plain steel studs and nuts for this
application anyway. It screams "corrosion". Why not heli-coil the port
threads and use a stainless bolt and lock-washer? That way, the threads
are protected from the elements to some degree and using stainless
hardware gives you a little better resistance to rot.

Any engineers know why studs are used on exhaust systems in general?

Thanks,
Mike

It is not true that SS is superior to other steels for all corrosion
issues. When you realize that SS has to be in contact with oxygen for
it's corrosion resistant layer to be maintained, you start to appreciate
why corrosion can be a big big problem (especially in sealed threads or
places where acids can form...)

-see http://www.corrosion-doctors.org/

Add some electrical current and/or salt and you may have a very big
problem when using dissimilar metals... Bottom line: Keep similar metals
together if at all possible and if you can't, make sure you know which
one will corrode and which can be easily replaced. A mild steel stud can
be cut, have flats filed into it or even be drilled out to effect a
perfect repair. No so easy in SS (especially when the stud eats the
metal it's screwed into)!

my 2c

Cheers MarkC