I'm guessing you have a later model (2001?) Cougar. All other Contours/Mystiques/Cougars do not have the primary cat checking o2 sensor.i would need an o2 cheater because there is still an o2 sensor after the y pipe hooked up to the main cat.
I can get Hi-flow cats. They are like 100 a peice.
Disclaimer added!!!!!
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