hello everybody ive been working on this and was wondering wot else u think i could do to it ?

Hey pretty good job dude! The front bumper looks strange good to me!But the car is only black and white and the bg - not, so my advice is to make the bg black and white too,it's the easiest way!Great job!Congratulations!

If i remember right, this ain't Z4, this is just Zagato Coupe. Im not sure, anyways. Looks nice so far!

Not bad at all, the initial concept is stunning and that new kit is looking nice..
not sure the car's reflections fit with a night time bg, and the black looks a little fake,
Try duplicating the red layer, setting it's layer mode to 'darken' then moving the hue slider for that layer until it starts to look black That way it won't be completely unsaturated

Keep it up

Not bad

on my chops i modify the car then change the background, would you advice doing it the other way round changing the background then chopping the base on a new background ? or is it a personnal perfernce thing ?

When you change bg first, you can make all reflections right at first time.