More than just tuning....
Let's say you want to run full auxiliary injection on top of your existing direct injection. Here's what you need:
- Intake manifold with port injection support
- 4x fuel injectors and a fuel rail
- An auxiliary injector controller. Depending on the controller you may need a crank signal interpreter.
- fuel pressure regulator
- Custom surge tank with 2x fuel pumps
- a whole buncha lines and fittings and
- a couple of relays
There's a reason not a lot of people do this...$$$
Oh, and after all that, then the tuning...