Hate to say it but baffled/chambered mufflers aren't that good at noise suppression and flow the worst of all the muffler designs. Yes, I know that's a bold claim to make and people swear by Flowmaster and I'm probably opening a can of worms I'll wish I never had, but I do base that opinion on research.

Autospeed Giant Muffler Comparison:
The mufflers
Detailed test results
Summary of results

Granted, Flowmaster wasn't included in that test, but ALL the chambered designs flowed the worst of the lot.

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Because they all flow poorly, when dealing with baffled mufflers noise suppression is probably the most important criterion. If this is the case, the Berklee BB3912 has very good noise suppression, although accompanied by a raspy over-run.


If noise suppression is your ultimate goal, I'd go with a 'turbo' style muffler.

My Truck: 1987 XtraCab DLX 22R 4WD 5 Speed Manual
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"Speed has never killed anyone. Suddenly becoming stationary, that's what gets you." -Jeremy Clarkson