Headers
I believe we talked a couple years back. Hmm... I am still interested in the beta test. Need to fit quite a few items above, depending on fuel delivery configuration/ intake and stuff. Some say that the stock tubes are engineered to provide the proper back pressure to the engine. It is true that you can over-do the exhaust. But in the case of the earlier BMW models, exhaust restriction due to the under-sized cast manifolds and down tubes, is certainly suspect. As an engineer, I believe in the mantra...air in..exhaust out, as efficiently as is possible. But , due to the nature of the 4 stroke cycle, or 2 stroke for that matter,some back pressure is necessary. Hence the term "exhaust tuning" as I learned as a yute, with expansion chambers and pipes on 2 stroke dirt bike builds. On a diesel application, i.e. the stove pipes we see on big assed pick-ups, back pressure is not an issue, but a liability, as is any application that utilizes a turbo. I could go on for pages. If any of my concepts are in error, please feel free to comment, you all, knowledge is a gift.
Nice job by the way, looks good to me.