Sepp wrote:

'Old style' ecu tuning with additional electronics unit wired to the ECU and sensor harness still does work though. It's just very few suppliers left providing those as everybody has been jumping on the train speeding into the brave new digital world.

Tuning through a diesel through add on devices is not true tuning in that you are not optimizing fuel maps for efficient operation, you are simply tricking the motor into 'overfueling' under load. This is done through methods such as increasing fuel pressure at the injectors by reducing the pressure value provided by the sensor so that more fuel is injected during an injection cycle than the motor ECU has called for, or falsifying the signal from the motor temp sensor so that the ecu goes back to cold start mode, etc. These are the cars you see with black back-ends from the soot...

The only way to truly 'tune' a diesel is to alter the maps in the ECU (in theory, you could provide a complete 2nd ECU with alternative maps, but I have never seen this done. And it would be very expensive...) 
RRC 2Dr, RRC 4Dr,
P38, and 2 L322s,
2 FL1s and a L663 on the way

Moo wrote:

So what happens when there is a software update or it goes into LR for servicing. Does the Map get wiped?

ed11oad wrote:

hi guys im a new member on here.
after buying a new urban 110 D300 back in april thinking it was the most powerfull diesel defender avaiable i have since found out that they make a D350.
no one seems to offer a power upgrade (remap) for the D300.
i dont really want a tunning module because they just dont deliver the stated power output.

any information or advice greatly appreciated