360 LA installing Promaxx Aluminum heads

Where is your o2 sensor located? And is the exhaust tighter than a dolphins ***? Like zero leaks?

Sensor is just down from the shorty collector as the exhaust straightens out. You can see the bung in the photo below from when I installed the exhaust. Exhaust is tight.

Reading manual for sensor... says should have re-calibrated after 3 months... I'm a bit overdue.

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