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Old 07-15-2012, 06:56 AM
Rob. Smith Rob. Smith is offline
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Quote:
Originally Posted by BMK View Post
I used the 'Summit' perforated inserts. They are pyramid shaped with preforations that match the internal pipe size so do not add any back pressure or restrictions.

They reduced my first test from 117dB to 110dB

Try sending a PM to Aussie Mike on the Forum he has completed a number of exhausts systems
7dB reduction is pretty good. I almost bought something similar but couldn't find any info about them; particularly noise reduction. What is the summit part number ? Did you measure from a metre at 45deg from the pipe exit ? was it at idle or drive past ?
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