My '99 has FF 640s and a non-return fuel system. As such, I do get some pretty wild variation on EGO, especially when idling and especially dependent on under-hood temps. In order to deal with it I'm using what I consider fairly aggressive PID correction for my EGO. I found that the fastest, precise, correction seems to happen when using the EGO delay table, meaning that the reaction time changes based on MAP/RPM.

My settings are:
P: 30
I: 65
D: 40

I figured out the delay at multiple conditions by changing the VE while driving steady-state and measuring in the log how long it takes for the change in AFR to show up. The delays actually seem fairly long to me- from about 700ms in idle and around 50ms (which is an estimate, not measured) in boost at 6krpm.

Is anybody else using this? With what level of success?

 

The EGO delay is largely based on MAP/TPS. With MAP ~30 I get a delay of about 2s, at ~80-90 it's more like 800-900ms.