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How can I reduce my exhaust by 2dB?

Advan_01

By Advan_01,
in General Automotive Discussion

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awurth Collaborator

awurth

Posted
Posted

cut a piece of tin metal the same shape as a flange and drill a couple of 12mm holes in it. it dropped 4DB out of my car but they run like real pov so go home and pull it straight away. if it's afully welded system just stuff some steel mesh up it and then put the silencer back in it. QLD it's 94Db.

GTR R32 Collaborator

GTR R32

Posted
Posted

If you just want to pass the test then the plate with holes in it between two flanges sounds like the best way to me. Another option would be to get an Apexi exhaust valve. It's a butterfly valve that you bolt between two flanges and it can be controlled by a cable in the cabin. So you can have it closed when you want it quiet or open when you want max power.

NXTIME Grand Master

NXTIME

Posted
Posted

I lost a few DB's by simply reducing the tip size. I went from 3" to a 2.5" tip and lost 4 dB's from memory. Cheaper and easier than a resonator. Otherwise, you may just have to add another resonator. Make sure that you get the exhasut shop to test the dB reading before you go back the the EPA.

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