I dont speak for generic chips but the factory ECU is never tuned for maximum results. It is simply tuned for NVH (Noise Volume Harshness), Economy, Driviblity, Reliability. Holden or any other company for that matter would not performance tune a family cars ECU then slap a 3 year warranty on it. R&D or no R&D. Holden used to play with numerous map's on the engine dyno, straight off the assembly line, if the particular motor ran ok, then great, they threw that ecu with it.
If you want to tune on a budget get a Haltech.
Onezero- What management system do you run in the supercharged 6? Im sure with all the money spent it would not have a simple remapped chip. They just arent tuneable enough.
Jake.