I have had my car on the dyno trying for a tune as i know it was pig rich...The tuner has made changes to the current tune and taken out 26% of the fuel...the AFR at lower rpms is good with the fuel taken out. but when it gets up in the RPMS it tends to lean out...he is after making numerous changes and the samething is happening. He said it seems like the ECM is not using the new changes...In the higher rpms the AFR reads lean but it still smells pig rich and burns your eyes..Any ideas? I am grasping for anything here now as the tuner is going back to his hometown in a couple of days.

The car is a 93, 383CI,12:1 compression, AFr 195 heads, custom cam, M6 with moser 9"

 

After you max your VE table @ 95-100kpa, (you should at about 3,000 rpm) you need to start using your PE (Power Enrichment) tables. With 30# injectors and 351 RWHP later (A4, mild cam, mild heads, stall converter) I had to increase fuel as much 15 to 25% from 3000 to 6500 rpm. The car achieved at 12:8 to 13:0 AFR.

If you car still has "Closed Loop" enabled tune, make sure that what you are seeing at the wideband is comparable to what you see in your pcm scan in the low rpm and low kpa areas. If you scan reads pig rich, it will bottom out our long term BLM (108) and affect your WOT fuel curve (takes out fuel). If you are seeing this, I recommend you lock out "Closed Loop", at least this way you know this cant happen.

Also, a lean condition smells horibly and burn your eyes, and true rich condition you would see black smoke.