OK apart from the obvious;
Which is better for my legnum? Or more effective?
Would I need to upgrade the BOV at the same time?
(I know this is really sad, but would to get a BOV that made the same sound as the original Dump Valves from the Sierra Cossie, , what can I say grew up in the time, when they first came onto the rally scene and just loved the ay they looked and sounded???)