Oxygen sensors on dual exhaust conversion

[Tharanga]

I am fairly conversant with EFI setups but this is a situation I have not come across.

I have a V8 engine with computer controlled carburetor (General Motors CCC setup) It has a single exhaust and a single oxygen sensor before the catalytic converter (cat). Oxygen sensor sits upstream of the cat. I want to convert this to a dual exhaust setup, but then single oxygen sensor becomes a problem (since the exhaust feed is halved now). Can I get two identical sensors connected on dual exhausts, now mounted closer to the engine (closer since heating is reduced now) and combine both sensor output wires to feed the computer terminal? Would this get the sensor output voltage up to the previous values?
Looking at the oxygen sensor output graphs, they are sinusoidal shaped meaning that the engine riches and leans the mixture based on the oxygen sensor voltage reading. Mixture is rich with the choke operation from cold start and even at the time the close loop starts (the voltage output from oxygen sensor is highest when the mixture is rich). So there is a risk of getting twice the voltage and resulting a CEL indication. However, if you really look at it, sensor probe gets heated gradually and the voltage also increases gradually.Therefore the computer will lean the mixture resulting a reduced voltage from both sensors before it reaches max voltage times two.
This is still my argument and I would really appreciate expert advise on this.

Thank you

Topic

[Alexander B]

Just stick with a single O2 sensor in 1 of the 2 exhausts, no problem.

[Mike]

Just talking out of my ass here, but what if you incorporated an “X” style crossover pipe? You could put the single sensor in the x.

Besides, the crossover would increase mid-range torque.

[Author]

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