Attempting to do some fuel economy tuning on my '01 Silverado 5.3L with a 212/212 114 LSA cam. I've upped the idle timing to increase vacuum and reduce fuel flow. And I've got DFCO set up pretty well.

I was curious what you guys would recommend for O2 switchpoints? Mine are currently 450 mV across the board. I've seen some as slow at 300 mV.

Does this essentially "trick" the PCM into thinking that it's running at stoich when in reality it's running a bit lean? Should I avoid changing the switchpoints if I were to enable lean cruise?

Thanks!