Well, I don't render myself, so I can't help you with the rim problem, but as far as the render itself is concerned:
- I would take a slightly darker light, for that dark blue car, to get a little less shining effect. Not much, just a little
- as a result of the former, the right sidepod and right side of the front (so, the back of the car by looking at this imagine) is way too bright. Either re-set the lights or make them darker in general
Apart from that, I think it's a very good render for your first time doing it. Hope this helps.
GPGSL : Team Owner of 'Maverick Track Performance' (MTP)