I have seen a lot of confusion over the past few days about the different types of tuning approaches, and a lot of people getting confused about which is what; So I made a quick list of the major types of tuning approaches an how to identify them.
I hope this helps! Be careful what you do, remember that use of EVERY SINGLE ONE of these devices will void your power-train warranty and that you will be on the hook for any repair bills that result of damaged engines, transmissions, differentials, etc. Also keep in mind that no matter what anyone trying to sell you something tells you, their use is always detectable one way or another. For example, if you install a device that modifies the map sensor output, raise the boost, blow your motor, and then remove your device in an attempt fraudulently get Kia to cover the repair under the limited warranty, They can and will be able to detected the modified MAP sensor readings ad the injector duty cycle will not line up with the reported map readings; and yes, all modern ECU's have at least some logging abilities.
- Stand alone EMS- A Stand alone EMS runs the whole engine, or the whole car. It sometimes will replace the factory ECU and wiring loom, or will be wired into the loom in parallel with the factory ECU. This is the best tuning approach, but also the most expensive and most difficult to install (unless an adapter harness / factory loom plugs are offered). They will include tuning software and normally will include features such as launch control, tunable traction control, anti-lag, etc. Examples: AEM EMS, Motec EMS, HKS F-con, Pro-EFI, etc.
- Piggy back ECU- This is an ecu that sits between the factory ECU, and the engine. It will read factory sensors and alter signal values coming in and out of the factory ECU. Most often they will feed dummy signals to the factory ECU to keep it happy, while directly controlling the engine. True piggy back ECU's will have direct control over fuel, timing, and boost maps at a minimum. They will include the software required to properly tune the engine and provide a near stand alone experience. Examples: MAP-ECU, HKS S-Con/IS, Greddy E-manage, AEM fuel and ignition controller, etc.
- ECU Tune- This is where the factory ECU maps are modified via a re-flash of the factory ECU. This is the easiest and often the cheapest true tuning option, as it requires nothing more than a map, and a re-flashing device; often tuning software is available; and it is highly recommended that you purchase a unit that allows custom tuning so that a local tuner can dial in your car with you mods. Examples: Cobb Access port, LSI-Edit, Diablo tuner, Super-Chips, etc.
- Sensor manipulator- This is the worst type of tuning, as it is not really tuning, these devices modify the sensor output of one or more engine sensors to "trick" the ECU; as no maps are modified, timing, fuel and boost maps are not properly tuned, as such you get less than optimal tuning results, and commonly, they can pose a much greater risk to your engine than proper tuning. Beware any sensor device that just plugs into the engine sensor harness, is not tunable, does not include tuning software and logging abilities. Generally.. these devices should be avoided and a real tuning approach should be used. Example: Pross Tuning Uncle Chip, and just about every "tune" that is being offered here.
I hope this helps! Be careful what you do, remember that use of EVERY SINGLE ONE of these devices will void your power-train warranty and that you will be on the hook for any repair bills that result of damaged engines, transmissions, differentials, etc. Also keep in mind that no matter what anyone trying to sell you something tells you, their use is always detectable one way or another. For example, if you install a device that modifies the map sensor output, raise the boost, blow your motor, and then remove your device in an attempt fraudulently get Kia to cover the repair under the limited warranty, They can and will be able to detected the modified MAP sensor readings ad the injector duty cycle will not line up with the reported map readings; and yes, all modern ECU's have at least some logging abilities.