Sould I get turbo piping made of stainless steel, coated or what? I'm more interested in longevity and performance. Cost is a factor, but $600-$700 more is not a problem.

 

I would go with a set of coated mild steel headers, unless you used thick (pipe) stainless, thicker than the typical thin wall gauge of 18 or 16. What I have seen with stainless is the headers will begin to crack and the region all around will be rather crumbling, brittle with a loss of ductility. The last time I heard about this was on a Brad Anderson powered funny car. They now use mild steel tubes with a silicon-bronze filler.

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