It's a pretty simple suggestion. Allow players to perform complete drivetrain swaps to ANY car in the game, except for certain cars like the Caterham Seven, Red Bull X-Cars, Formula GT, etc. Players have asked for the ability to set the torque split on AWD cars to 0/100 or 100/0 for a long time. It would open up so many more opportunities for tuners and players that actively engage in racing series. Drifters would love to make their Skylines, Imprezas, and EVOs 100% RWD. I am not sure what other types of players would benefit from this, but it would be fun to completely change the drivetrain of cars. Besides, who wouldn't want a front wheel drive Bugatti Veyron just for the fun of it?