Stumble on Acceleration with very lean readings from wideband

[S10Sanity]

Hey everyone to start off here is what has been done to my 1989 Chevy S-10 4.3 liter Vin Z Computer #1228062.
*All cylinders bored 30 over
*New Pistons (do not have in front of exact ones)
*Comp Cams Cam,Springs,Hydraulic lifters and Roller Rocker arms Part # 09-420-8
-Camshaft C43 270H-R10
*96 and up Vortec Heads
*2114 Edlebrock Performer Intake manifold
*Stiffer spring in TBI Regulator that pushes pressure from 13 to 18.

The Prom I have in the computer now is the stock prom with Main Spark table changes to more of a vortec type table and EGR dissabled. The problem that I am having is that when I fire her up she runs good at idle nice and smooth. I throw here in to drive and head out and for the most part runs fine no problems until I try to accelerate with the pedal more than half way down to WOT my truck stumbles and hesitates but then if I just give the pedal a little push it gets going accelerating normally. My wideband 02 sensor shows a really lean mixture during the stumble like somewhere around 22.3. I have attached my latest data log its not way long but shows the problem. Thank you for the advice and opinions in advance im pretty much at a loss at this point.reference.