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Has anyone used a 4 wire o2 sensor calibration on a car that has 2 wire o2 sensors & if so is there anything in particular to alter?

I use 4 wire sensors in place of 2 wire wherever possible, normally due to using extractors and the sensor is placed further away in a cooler location. Just add the +12V and additional earth for the heater circuit, don't connect the heater circuit directly to the same earth as the sensor circuit. All the Bosch narrowband sensors mix and match fine (assuming they physically fit in the exhaust boss!)

I saw a VP HSV with a 4 wire sensor recently and it has an extension lead which plugs into the 2 wire plug, adds an earth from the back of the block and +12V from the coil terminal. Looks quite neat and no cutting of wires, I'm guessing it may even be factory HSV?

edit: what do you mean by calibration, have I gone off track here?

LOL, no that's a great response not off track at all!

I just meant if I don't add the heater circuit o2 sensors should I change anything in the tune.

I think there are some o2 sensor warmup time settings you could look at if they are defined.

Thanks yeah I always tweak them anyway as bigger zausts normally screw them up too!

there is a timeout value and also a voltage level trigger the o2 sensors has to pass before enabling Closed Loop BLM. Pretty much 2 wire sensors have a longer timer limit to warmup. Should be these scalars.

Closed Loop Determination - o2 Sensor - Not Ready Timer Limit

Closed Loop Determination - Upper o2 Threshold (o2 A/D Units)
Closed Loop Determination - Lower o2 Threshold (o2 A/D Units)

LOL yeah they look pretty familiar as there the 1's changed for bigger exhausts too!

Thanks everyone for the tips!