The thrush welded that I've ran we're both pretty deep sounding... I can't say they were alotta quiet though lol. Hard to tell in my applications though. One was duals dumping under the rear seat of my 83 ram charger (can't remember size), and the other was a single 3" no cat dumping right in front of the rear axle under my burb. The burb sounded amazing and wasnt super loud inside, but would literally set off car alarms rolling through Walmarts lot.
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