What size carburator should I use on a 1985 stock 318? It has a stock roller cam and a new Edelbrock dual plane intake manifold. We have taken a lean burn two barrel system off the engine and want to place a four barrel carb in its place. Anyone have any recommendations? I would prefer to use a holley if possible. AND do I need to have a full 12 volts going to ECU in order for the Mopar electronic system to work?