I am fabricating a stainless steel exhaust downpipe, or should i say i will cut out all the components, tack (or maybe tape) together then have someone purge and tig weld it, until looking into whether 304 can be used alongside 316 i had never really given the grades of stainless steel much thought, this exhaust downpipe will be used on a turbo petrol engine, which grade of stainless steel will be most suited to the heat, offer the best corrosion resistance and offer the best resistance to cracking, lastly i think i will struggle to get certain components (v band clamps, flexible joints etc) in the same grade will this matter? i would appreciate the imput of those in the know thanks