What setting do you have your Boost a Pump at?
I did a few dyno runs this week and the air fuel was a bit lean.
The manual instructed to set the pump at 10.
After turning it up a bit the Air fuel got Richer.
I ended up leaving it set at 20, that is where my motor seemed happiest.
I sampled the A/F from the existing 02 bung(2nd one)
58* made 370 RWHP and 360 RWT low eleven A/F