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      07-21-2008, 04:50 PM   #25
GregW / Oregon

Drives: 2015 M4 Coupe, 2012 ML350
Join Date: Nov 2005
Location: Lake Oswego, OR

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Originally Posted by kyoshozx View Post
I agree with most that exhaust prices for the m3 is a bit expensive. The thing that bothers me about eisemann is that it's just a muffler and doesn't include piping to get rid of the really bad crimps in the stock piping.
And why do you think the crimps are bad? You would intuitively think so, but from my architectural practice I know ductwork can be flattened for a short distance, to go under a beam for instance, with negligible loss in performance.

Edit: In duct design, which has many of the same issues as exhaust system design, the situation above calls for an Obastacle Avoidance Fitting (OAF). If this is done correctly, there is an increase in static pressure going into the restriction, but it is almost negated on the outgoing side.

Greg Lake Oswego, Oregon, USA
2015 M4 Coupe - Silverstone/Sakhir/CF
2012 ML350

Last edited by GregW / Oregon; 07-22-2008 at 11:23 AM.