Hi all!!! I need to install an external wastegate to my car but I don't like to use s/s exhaust manifold because it is not durable. I need to keep my standard 4wd cast one but I'd like to know which is the best and most durable way to weld a pipe (and also what kind of material for the pipe) on the manifold? Also what would be best; MIG, TIG or ARC? Also is it better to weld it preheated or cold? Cheers!!!