the only way to get a quieter exhaust is going to require deleting the B&B entirely and going with an actual muffler.
I watched a 800rwhp viper with full exhaust (MUFFLERS!!!) take off from a meet once. it was AWE inspiring to see this thing just rocket off like it did, and not even hear it. it was like watching NHRA pro drags with the speakers off. Far more impressive if you can experience it in person.
"As the Z32 gets older and decreases in value it becomes affordable by lower income and often less desirable people whose tastes reflect their personality and social standing.- Marshall 17:37:05 10/10/03