Originally posted by slim speedy
Who said anything about using a RS ECU for a WRX swap? You can't, the redline is the least of the issues, it has no concept of boost or fuel maps for a turbo. It either won't work at all or it would blow the motor. Some people use an aftermarket ECU like the link, but most people use the stock ECU from the model of WRX the engine came from.
Ahh, the boost and fuel issue was also brought up in one conversation. If the engine and ECU are from the same car, why is there such a problem with wiring? Is it from all the accessories (lights, dash, wipers, etc)?