Grey Mod, quick edits of both the car graphics and the settings to make the game both harder and have a slightly different look.
Not much harder, just sorta feels different.
Just replace the cars file and the settings with the ones in the .zip, backups are also included incase you want to revert to normal.
Now with new sounds! Backup not provided, all sounds provided in this mod are License-free, created by... Well, me. Except a couple that were just the existing sounds with filters/distortion/reverb/Pitch/formant edits. Missile sound was unchanged, game crashed on every attempt.
Preview of some of the sounds here.