The GM DIS module is a digital distributor. Its feed the crank speed signal (with a reference pulse - so 7X) directly, When running in bypass mode it runs on a fixed timing, this is for cranking....

Its my understanding that GM didn't use full sequential on most ECU's until 94-95, and then the hardware still could only support it up to 4000RPM, and batch fire takes over. I would look for a Quad...