LT1 8051 tip-in lean? Anybody had success curing it?

[sherlock9c1]

Anybody in the 8051 world successfully dealt with the LT1 tip-in lean without scaling the MAF values, injector flow rates and cylinder volumes? I am tuning a bolt-on '95 motor with an intercooled Procharger setup with updated fuel system, GM MAF and fully characterized injectors. It's currently in MAF mode and the owner would like to keep it that way. The car starts instantly, idles perfect, and pulls like a freight train, but it's got a terrible tip-in stumble at idle that's particularly pronounced while cold. We've got a wideband on it and it's showing it goes immediately lean; no rich at all. During the rest of driving, the AFR is right where we expect it to be and the motor is well-fueled right up until redline (self-imposed around 5500rpm when we run out of injector). I have tried adding lots of fuel to the VE tables in the stumble areas but it doesn't seem to have made a difference.

Interestingly, I took a bone stock LT1 Roadmaster wagon, started it up, whacked the throttle hard and it seemed to have quite a bit of the same stumble!

I've read a number of other forums and many forced induction LT1s seem to have the same problem, and they all solve it by scaling the above values pretty severely, perhaps under the theory that the $EE has a tip-in enrichment that is nonadjustable, or at least nobody has found it yet. I did try a "half-MAF" tune where I scaled everything per above, and the car started, ran and drove decent, and seemed to have much more oomph during tip-in, but eventually the PCM learned it back out.

I'm wondering if perhaps any of the remaining mystery tables in the $EE definition might be something along these lines, perhaps a tip-in enrichment vs. coolant temp vs. rpm? Anybody playing with this? How many tables or areas in the $EE binfile are still "mystery?"