The Great Bungholio, Where to stick it Options

[Porschef]

My AFR gauge arrived yesterday and I was all amped to install it today. A few weeks back when I installed the sway bars I welded in a bung for the O2 sensor in the stock Leistritz muffler in anticipation of this day, however, it appears I may haven't enough room to install the sensor without cutting sheet metal.

Ain't gonna do that. The kit includes a bung so I'll just abandon the prior unit with it's plug, and weld in the new one (Oh Paul, where art thou ;-)

Question is, where? I know it's gotta be between the 9:00 and 3:00 positions, but would it behoove me to place it near the exhaust tip, or is anywhere else ok?

Anyone face this dilemma?

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Thanks,

Joe

[Mike Bellis]

Heated wide bands will start to fail if the temp around the sensor stays above 800°F all the time. They sell a copper heat sink for these to dissipate the heat. You could build one yourself with 1/16" copper plate. They mount like a large washer between the sensor and bung. Aluminum will not work as well because unlike copper, it will not draw heat (conduct) as well. An aluminum heat sink would cool down fine but not draw the heat from the sensor.

A non heated needs to go closer to the head in order to heat up. Once hot they read the NB pretty well. Most installation instructions state to mount the sensor close to the head. In a T4, most mount on the header collector for best cylinder (4) reading.

On a heated wide band, You can mount it near the tip but as said above, it can read the atmosphere if too close to the end. In this case, as close to the muffler, on the lip elbow would be best.

Most dyno tuners use a tailpipe wide band for tuning. It inserts into the tail pipe 6". So I would use that measurement as a minimum from the end of the tip.