For a BCC engine conversion, there are currently two choices for fuel control and ignition.
The engines we are using should already come from the factory with sensors, injectors, coil packs and wiring. They would have been controlled from the same ECU that controls most everything in the donor car, from ignition timing to vehicle security, to courtesy lighting. What is required is some way to control just the engine and not bother with the rest of the system.
The first option is to use a modified GM ECU with a matching harness. These ECUs have been set up to only control the engine independently of anything else it might have controlled originally. These ECUs have programmable chips that can be swapped out to further tune engines for specific installations. The harness comes pre-terminated to hook up to the engine and to the vehicle's wiring. Approx. $900
The second option is to use one of the new generation of aftermarket ECUs. There are many out there, but I feel the one with the most potential is the open-source MegaSquirt project. An ECU, relays and wiring harness kit can be had for about $500. Bear in mind that this is a universal ECU and will require set-up for each engine. Harnesses are in kit form, and will need to be routed and terminated.
For someone looking for a plug-and-play ECU, the Wade ECU from BCC would be the better choice. For someone who likes to tinker a bit, the MegaSquirt offers on-the-fly tuning via a laptop PC and the ability to route the wiring and locate components as desired.