I'm not sure which setup is the loudest. I think the Dynomax muffs that come in the Classic Design Concepts
www.classicdesignconcepts.com side exhaust kit are louder than mine (I have the Borla Rebel 500 side exit) and I have never heard the Rousch setup. Generally Hpipes are louder than Xpipes. Check my sig for a sound file of the Borlas. I still have my stock Hpipe on so it is more mellow than it is loud but it's still more aggressive than stock.
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66 Tahoe Turquoise Coupe
Laser Red 96GT Ragtop
30 Years & 30 inches apart in the driveway!