I'm willing to bet on two things:
1. Timing
2. Your BOV is set to vent open, fast and furious style (which explains the bogging)
Hijacker wrote:If you want to stick with the ka ecu and distributor, JWT can reflash it for you to make it work properly.
Also, the bog you're having is related to the rich condition.
Personally, I would try to get ahold of an SR ECU, wiring harness, and ignition setup. Distros are fine and all, but for a turbo setup direct fire ignition is superior
Our stock ignition system isn't exactly known to be the best as far as coilpack setups goes. It certainly isn't a GM setup for sure
The KA distributer mod (which JWT actually outlines in thier FAQ section) works extremely well, as is just as good/reliable.
However, good point about the ecu not being tuned for the injectors and or MAF....another good thing to look for.