AFR Location

For anyone running an AFR where on the exhaust did you tap into? Ideally in front of both cats but with DT Headers there is practically nowhere to weld a bung onto. AEM instructions say to give the sensor a +10degree of tilt to allow condensation to escape sensor, not sure it is possible with my current setup. Thinking about putting behind the 1st cat but from research it sounds like this will throw readings off +/-0.4 — Not sure if this is a huge deal or not. Could drill into the cat right before the filters but doesn’t sound like the best idea.

 

I'd put it in the collector near the original. You won't have to worry about condensation as the collector is facing downward. If you're hesitant to drill into the header, I'd fit it before the cat