[petek]

I'm using a Holley Projection 4Di system that has an O2 sensor. I mounted my sensor in about the same spot as Scott did in his picture above.

I talked with the Holley folks about monitoring only half of the cylinders (i.e. a single side pipe). They said that it will work fine.

My experience so far is that the O2 sensor warms up very fast, under a minute for sure (as monitored by watching the O2 reading on the screen of a laptop computer).

I haven't had any indication that airflow over the external part of the sensor is cooling the sensor to any significant degree (my sensor is tucked up pretty close to a frame rail under the car).