Pelican Parts Forums - where to pout O2 sensor

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where to put O2 sensor

I have my header off and for sale and was going to have the joint where all the pipes come together at the turbo tig welded but I would like to add a place where I can measure exhaust gas back pressure.
I was going to put the bung right there below the turbo but I was thinking the better place to know the exhaust back pressure might be at #3 or 6 exhaust port since the pressure of the exhaust going back into the cylinder is critical.
I have seen a back pressure gauge on the 935. Where do they measure it.

If i don't sell the header soon I may change the cams since I have the engine out

Anywhere before the turbo is all you need since pressure is equal throughout all places. If someone has a better reason to place elsewhere, I'm all ears.

Do you mean exhaust backpressure, or AFR's???

:confused:

Back pressure. Curious what is. Could effect what cam put in there.