Yes you can have a ECU calibration that will dump fuel on de-accel
It is a popular request from Gallardo owners.
Keep in mind the following

1. For a car to shoot flames it has to have been a very high rev range prior to it starting the shoot flames (long wot pulls or high reving fora minute or two when stand still
2. Harder to produce flame with a stock exhaust system. After market system with a straight flow through design with resonators will produce flames sooner
3. Try no to do this too much because the cats will get damaged eventually



2.