Although it doesn't have any tuning slot, I have introduced a 18-speed transmission. Along with it a new radiator, intake, and a T500 turbo. This new turbo pushes 70 psi, the intake give loads of power too (I didn't measure it), and the radiator is almost required if you want to use all the new things at the same time. Enjoy!
Alpha Gavril TCX i6 Diesel for D-series 1.5
The semi engine has been swapped into the pickup truck!