why are you posting about agency power headers...?

oh yeah and if you are going to go with a non BMW name brand like supersprint, or evosport...

save yourself the issues and just buy the exact same headers off of ebay...

$150.. I am running them right now with a Magnaflow cat-back exhaust. sounds great, no leaks, no cracks, use my own o2 simulator so no check engine (when i am on the track, and I never drive on public roads with any alterations to my emissions systems).

lots of great stuff on ebay.. once those companies outsource their design to overseas manufacturers to take on more demand.. those overseas manufacturers produce at such a low cost they actually take over all production and all they ask to be able to use the design to sell directly. may or may not be the case with the ebay headers but those are no back of the garage headers... mandrel bent t-304 stainless steel with impressive welds.. thats some damn good quality for $150.