The long time members here know that I am a hardcore Alfa performance enthusiast. For a long time my company offered hiperformance parts for the vintage Alfas. We still do, but over the last couple years we have been adding parts for the newer cars as well.
At the retail level we have merged our product line with Eurocompulsion.net so all the stuff we make for the 4C is available there. Of course you can always contact me directly for tech support, just know that I can't sell these products at the retail level.
We have a 4C ECU swap option that really adds a lot of power. It's been well received by our customers. Unlike a flash tune it can be returned to stock by simply putting the original ECU back in and there won't be any footprint left, it's an easily reversible and undetectable mod.
Our ECU uses official Alfa software and even if it's scanned by the dealer it will show the correct factory software number. It will also work seemlessly with any other aftermarket modules that control transmission or other functions because it's seen by the car's other modules as the correct factory part.
Here is a picture of it as well as some power information. Keep in mind this was with a Novitec exhaust, which I think adds about 2-3 hp and looks great.
link: EUROCOMPULSION PERFORMANCE FIAT ABARTH 500 500T and DODGE DART PERFORMANCE PARTS