Supertrapps?sounds to me like he is describing those mufflers from the late 80's where you could stack different amounts of plates in the end of the muffler to change the sound..
i forget what they were called, but EVERYONE used to run them on their Pro-Streeters back then.
Could you elaborate on the appearance of the exhaust system? Did it have a "Y" junction with one tailpipe open and the other capped and both about 18" or so long? If it is like I described could you find out who makes it, because if it is this system uses "interference" tuning. This interference tuning reduces noise and increases the length of the low pressure pulse at the exhaust valve, so overlap scavgening will occur over a wider rev band which is a very good thing. In other words more torque over a wider RPM range. The only bad things are the strange appearance and the extra bulk.A while back I saw a few Mustang guys that had the tips of their exhaust plugged up. Doesn't make sense to me. Won't this damage the engine by restricting its ability to breathe