Testing coils on a coil over plug system?

[art leong]

I'm having trouble keeping it running when putting the car in gear. Have changed the converter (no help). Checked and recheck all wires and grounds. Changed the fuel filters (no help). Done a leakdown test (2% to 4%), looked at the top end, all cams and running gear look okay. Checked plug wires 27 to 29 ohms resistance, new plugs. Double checked timing.
When I drop it in gear it just gets crappy and stalls. I've data logged it and there is nothing showing that could cause this. What ever it is it seems to have gotten worse, before I could keep it running with the gas pedal but now it is almost impossible to keep running.
It seems to get worse as I work on it. Then get a bit better the next day.
There are no vacuum leaks, when I put my hand over the intake it reacts immediately.
I've played with the tune (richening it or leaning it) and it doesn't seem to change much and doesn't get better