Exhaust Flipper Valve Tunning

[Samuraj]

Just to be clear , how to “improve”with out any hardware,

 

[CrashTestDummy]

For the education of the unwashed masses, what are those found on? I can only figure that might be on our '25 Sierra 6.2, but haven't run across that on our '18 PPV.

 

[Samuraj]

Oops , came from my 2019 PPV
Only small improvement noticed , so Flowmaster have to came in to help