Looks great, i love these works where you brush the bg/modify it alot!
however there are a few remarks that will make it look abit better in my eyes.
* - The front lip feels like its "turning" abit too much to the left ( where the left vent is ).
* - The car should be a little bigger i think, it feels abit too small now.
Thats pretty much all i can think off now
But keep on working!