Made from stock S2000 exhaust pieces and a few other pieces. Stock resonator used for muffler. Weighs a bit less than 20 lbs. Sounds great. This meets 93 dB sound limits for places line San Diego Qualcomm Stadium. It registered at 91 dB at one of four SD National Tours. Otherwise it registered less than 91 dB.
Aug 2010 - cut it off and added a v-band joint to allow removal when running autocross events. A short down pipe is put on in it's place. This provides an additional 10 lbs reduction when running autocross. The sound level has not been measured, but it meets the < 100 dB requirements of SCCA autocross.
April 2012 - built a new single cat back using the stock exhaust cut at the Y with v-band installed. Twin loop muffler purchased on ebay for $70. Goal was to be 93 dBA compliant for San Diego. Twin loop version weighs 20 lbs. The piece after the v-band weighs 9.5 lbs including rubber hanger. The twin loop version is much quieter than the old single using a stock resonator as a muffer.