Still reckon that Italian tune box thingy is little more than jsut increasing fuel rail pressure so that it just dumps in additional diesel at any given Rpm range by modifying the voltage.
The power curves on the previous graph are exactually the same as the original map. Just with increased fuel.
To me that just shows its a linear map. Its not smoothed out any or the power issues or torque curves. Just increased them at a higher power level.
In laymans terms yes it will deliver more power. Just its effectively overfuelly the car to get that power.
Fortunatly diesels you can do that as there is little chance of detonation with how a diesel car works.
Personally I'd opt on paying someone like Gus who can specifically tune the car to how you want it.
Yes it costs more but I bet the power delivery is much better and more improtantly isn't over fuelling the car to make the extra power.
I know its alot more but there is no other method that for £300 ish pound will you get 20% increase in power and torque just by plugging in a computer.
If I wanted to increase power by that much in an N/A Car I would have to buy Cam's / port head / raise compression, change the fuel type change tappets to mechanical etc etc. well into the £1000's.
So for £350 if you can afford it i'd opt down that route.
Article on just increasing the fuel pressure on common rail diesels.