This is a Sound and Performance boost activated cutout seen here:
http://www.spracingonline.com/store/SP_Exhaust_Cutout_3\___Boost_Activated_/3673
When over 6psi the cutout opens up - here's my video on it working on my stock downpipes with a bad H pipe install and on 91 octane tune at around 12psi. I haven't had a chance to test it yet with the new 23 psi tune. Previously this cutout picked up .2 and 2 MPH for me in the 1/4 mile in back to back testing. I like this versus a loud exhaust so I can have a quiet exhaust 99% of the time and loud when I want it.
Ford Flex with exhaust cutout - YouTube
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http://www.spracingonline.com/store/SP_Exhaust_Cutout_3\___Boost_Activated_/3673
When over 6psi the cutout opens up - here's my video on it working on my stock downpipes with a bad H pipe install and on 91 octane tune at around 12psi. I haven't had a chance to test it yet with the new 23 psi tune. Previously this cutout picked up .2 and 2 MPH for me in the 1/4 mile in back to back testing. I like this versus a loud exhaust so I can have a quiet exhaust 99% of the time and loud when I want it.
Ford Flex with exhaust cutout - YouTube
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