If i get a 70mm test pipe and exhaust? do i need to mate up a header with a 70 mm collector
if I plan on getting a 70mm test pipe and exhaust, I would want a header that matches that, correct? Correct me if I am wrong, but my understand was it was always best to have the same size piping through from header back.

Thanks

 

no you dont need to match, it still works fine, bc either way and if you think about it the 70mm would fit into the stock header and work.