For the AMX I use the DynoMax CVX mufflers with a X pipe. The dB for these mufflers is 82 compared to 86 for the Borla and 92 for the Flowmaster. Measurment at "Half meter static test @ 3200 RPM " The sound level is reasonable , not offensive , both at a steady highway speed and when accelerating, taking into consideration the rear exit for the exhaust.
I contacted Dynomax Tech Services and mentioned the need for a street Cobra side pipe muffler and as a starting point used a length of 28 to 30 ", 4 " round case, tapered at the ends to 3" For the dB level I used the CT standard which is:
CT DMV Section 14-80a-4a , Allowable Noise Levels since Jan 1, 1979. The maximum dB for a stationary test is 72 dB for soft site( grass ) and 74 dB for hard site ( pavement ). Section 14-80a-9a mentions the distance for measuring the dB. The baseline is 48 feet or more but less than 58ft. An adjustment to the dB reading is made up or down for readings either closer or farther away than the baseline range. The max reading is 81 dB for a hard site, highway operation above 35MPH, using the 48 to 58 ft baseline for measuring.
Received the following reply from DynoMax:
From:
ta-walkertechline@Tenneco.com
Subject: Dynomax Exhaust
Date: August 23, 2006 1:45:54 PM EDT
Thank you for your inquiry for Dynomax Exhaust. We appreciate your
interest in our products. In regards to the muffler design you are
requesting, we have no immediate plans on releasing such a product, however my engineering department has been given the requirements for future consideration.
If you have any further questions, please feel free to contact our tech
line at the number below.
Thank You,
Lisa Kortz
Dynomax Performance Exhaust
Installation Technician
Tech Line Number
1-734-384-7806
Should anyone else desire to contact DynoMax, the more inquires they receive , might someday make the muffler
http://www.dynomax.com/tech/email.asp