Kevin

It looks like you need more fuel. However where are you mounting your O2 sensor for the dyno?

If it's out the tailpipe your readings will error towards lean. Measure AFR's precat.

Motilev

Hi, Kevin!

Yes, we mount O2 sensor inside tailpipe. Now I am going to install PLX sensor and then show how it is works.

Which better place to mount it? My car hasn't cat and secondary muffler - a have free flown muffler instead stock cat. You can see it in attachment.

So need yours advice where mount O2 sensor.