Aftermarket turbo exhaust manifold?

slantsixdan said
Well, I certainly wouldn't argue with expert consensus. Seems a little odd to me; O2 sensors are routinely subjected to much greater heat than it seems likely you'd have at that location with that engine, but I wouldn't want to be the one paying to clean up the results of being wrong on that point.

I share that concern about where the turbo's gonna wind up in that '64 Valiant.

It's not just temperature - their accuracy is affected by pressure, too. The temperature in shorter headers would be likely to kill the sensor, but even if the temperature is within acceptable limits, the pressure will make it very tough to get an accurate reading with a wideband O2 sensor.