There’s a scary rats nest of wires behind the dashboard as well as throughout the car. If you follow the wiring path, you’ll find many wires take several detours on the way to their destination. That’s fun if you’re talking about back roads and an afternoon drive, but not what you want for an efficient electrical system.
Given also that I need more/different wiring to handle all my modifications, and that the original wiring (not to mention fuses) were barely adequate for a stock vehicle, I elected to rewire the car from scratch. I started by running 2/0 welding cable from the battery to the starter, and created two new wiring panels, one at the front and one at the rear. This reduces the amount of front-to-rear wiring, and cuts down the rats nest of wiring from trying to run all circuits in the car from a single panel. I re-purposed the original starter cable to feed each panel. Each panel houses a Littelfuse universal style waterproof relay/fuse box that uses Metri Pack 280 style connectors and can be configured for a mix of blade type fuses and compatible relays.
I’m using dual circuit Blue Sea junction boxes to feed circuits that are 1) always hot and 2) hot on run. A separate relay (not shown) energizes the hot on run circuit to remove the current load from the ignition switch. The front panel (below) will run radiator fans, wipers, lighting, horn, windows, heater blower and accessories. My primary headlights are HID and run off their own controllers.
The rear junction box circuits are 1) always hot and 2) hot on run plus start. The rear panel runs the fuel pump, coils, injectors and ECM. I’m using the stock Acura ECM for now, but AEM makes a nice aftermarket unit that I plan as a future upgrade.