97 7.4 liter mpi

I have the above engine with stock exhaust and I would like to measure the fuel/air ratio, can someone explain how to accomplish this with the stock wet exhaust.?

Thanks

Brian

A/F ratio is measured using a wide band O2 sensor in the exhaust. To accomplish this, you would have to have a fitting installed into your exhaust manifold that penetrated through to the exhaust and sealed in the water jacket. It would be like a sleeved fitting into the exhaust stream. I have never heard of one being put into a factory exhaust before. CMI will put them in their tail pipes upon request for a fee. The sensor has to remain dry or it will not work.

Correct info, I have EMI exhaust with long risers and I had them weld in O2 bungs from the factory. Another method is to install a bung right at the exhaust port of one cylinder. This method eats sensors and is not very accurate.