Rebuild kit for your Silent Touch or Quarter Stick. If you track your car alot, eventually every exhaust uses up its muffler. The advantage of the BOE / BWR race muffler is that it is rebuild-able. Unbolt your exhaust, pull out the 3 bolts on the cannister and stuff in some packing material. For the quarter-stick just stuff some stainless steel scrubble into the silencer and bolt it back together. Similarly, with the scrubble and fiberglass for the Silent Touch. You do not have to replace the existing material, just add to what is already there.

To freshen up your Quarter-Stick one bag of scrubble should do it. For the Silent-Touch a bag of scrubble and a bag of fiberglass and you're back on the track!