That photo doesn’t appear to be all that sharp because of the panning, that said the slightly turning angle of the car can make panning tricky at times as I’ve found out when I’ve shot motorsport etc.
The exposure seems to be spot on, the composition isn’t bad either. It just needs to be sharper really, and panning just takes practise and then remembering what technique worked to get a good shot and repeat it.
I’d also aim to get some more interesting angles/compositions, while this photo would have been good (if it was sharp) there are many, many more like it out there. I’ve done it myself where I’ve taken generic motorsport photos and they’ve been reasonably good, but its far more rewarding when you envisage a challenging composition or angle and you manage to pull it off after quite a few attempts.
An example of my above point is in this one from Brands a few weeks back. I had to do many, many takes of this shot to get the cars framed by the tree correctly, as well as sharp (taken at 1/30th), and then the correct car(s)-
BTCC Civic Estate And Focus by
Niall97, on Flickr