[ss3011]

If you key on the DFI controller it should cycle the fuel pump for a couple of seconds then turn off until it cranks sees engine rpm above a certain rpm. If fuel pressure doesn't build up enough and you crank too soon, it might not build enough fuel pressure to run. I used an Accel conversion pressure regulator on my LT1. It used to hold full pressure for 30 mins or more after shutdown. You either have a leaking regulator or dirty fuel injectors that are leaking down. Also is your Opti-spark still hooked up ? There should be a connector in the Opti-spark that picks up the signal for timing the fueling. Depends on how your DFI is configured. Might want to check the connectors and wires. Does your Opti-spark have the ventilation system installed ? The later Opti-sparks had a vent system to prevent moisture from building up and corroding the components inside.