i'm seeking for that kindy of filter too.once i saw one name ARC fit in K20 engine(civic 2.0).i'm owning D17(civic 1.7).Well, does the ARC filter fit in D17?anyone there know where can get such filter?
Ok,found this article about how to make twin muffler/exhaust system that is consist of s-flow and straight flow at the same time.
but the problem is i dont know where to find the parts and if i can use another part...