that happened to a friend of mine's car a few months ago. he had a 96 b18c1 swapped into a 93 hatch. his problem was a couplea things:
1. intake manifold was cracked
2. secondaries were fucked up
3. loose wires on the dizzy
he used the obd2 distributor that was on the motor, and just hacked it. all he did was buy a new manifold, remove the secondary butterflies, and then double-check all of the spliced wires on the distributor. works fine now.
but his did exactly what you're describing, bog down around 3k.