I put the 16" JCWhitney tapered shorties on my '03 TBS. It's loud enough, but doesn't set off car alarms. Eventually I'll rejet, but it's okay w/o it, just a little megaphonitis from the mid 3's to 5 grand. At $32 per muffler, you can't beat it.
Steelheart- '03 Speedmaster Black/Yellow
The Hayabusa Killa
16" Shorties/140 mains/Airbox drilled
Procom CDI
"There is no cure for Celibacy. But we can treat the symptoms."
