As we all know the factory ECU can be re-tuned via a handheld programer. I upgraded from the SCT 3 to the SCT livewire. It has built in gauges on a 4″ screen and holds up to 10 different tunes versus 3 on the regular SCT 3 and 4. Plus it reads and erases DTCs. I picked this unit up from the guys over a JMS Chip. They do a lot of tuning and recommended this unit for all my tuning needs. You can see it in my track videos.