O2 sensor placement
Narrowbands are slightly less fussy.
Turbo, place the wideband some 12"+ away from the turbo.
So pre-turbo would be a very bad choice of location, as the sensor will not survive.
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You can buy little extension pieces to lift the sensor out of the gas stream, and some of these have cooling fins on them to try and help dissipate some heat prior to the sensor.
eg
http://www.innovatemotorsports.com/x...cat=250&page=2
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