Hey,
This is a render of a Porsche 911 GT3 RS which I finished modelling recently. Everything apart from the fog was made in blender and rendered with cycles.
I started using blender one year ago and I want to improve my blender skills. Therefore I would be glad about some honest critique… 
Thanks, RR
Rendering and post-pro looks really great imo, tho I’m no expert. On the modelling, topology seems really good as well. Problem is, you didn’t quite get the shape right. I’m not sure if you didn’t use blueprints after all, but I would strongly recommend it. In case you did, either they were miss-aligned (which all blueprints always are, but really little) or you just didn’t match each vertex on all the axis. Also, I’d add some depth to those rims and make the mirrors bigger. Appart from that, I think the fog should be perpendicular to the camera, not aligned with the stripe on the road, which I think creates a weird effect.
Harsh critique done, I must say your work’s got some quality, and I really like the rain effect, which I think is really realistic.
That’s all. Keep improving!
Thanks for your reply! You helped me a lot with your comment about the size of the mirrors and the fog! Unfortunately I didn’t use any blueprints which was a mistake. Next time I modell a car I will do.
Rain on the car body is simply wonderful, I keep zooming in on it! The front spoiler and wheels seem dry, though…