Would the dealership find out? When I had my XFS the forum for that model was sponsored by a company called Spires which apparently had a good reputation for remapping the V6 diesel & increasing its power from 275 to 305bhp for around £850. This included re doing the work if a dealer ever changed it back to the original state. Not something I ever felt the need to do because I'd had too many engine problems with the car from new so once Jag had eventually ironed out these I didn't feel it wise to mess about with things.<br />Be nice to have a V6 F-type that goes like a V8 though!