May be a dumb question but, inside the tube, the perferations only are open from one side? Are these reversable? My truck has a similar set with the perferations open to the rear of the exhaust and that is the only way that they could be installed. Does the sound just bounce around in the tubes entering from any direction? It would seem to me that the perferations should face the engine as to absourb some of the exhaust? Is this right?
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