Here is a before after of the first level of grading.

Everything was rendered with quite a dull flat render, without too much contrast. This meant that we had more dynamic range to work with when grading, as we weren’t using 32bit.
This was the first stage of the grade, that was worked out at a very early stage. It was actually first tested by bringing a tiff into Adobe Camera Raw and applying the kind of editing I would normally apply to a DSLR photo. I could change white balance and exposure, and add camera defects such as vignetting and abberations.
Once we were happy with the first pass of grade, that look was copied as closely as possible in “look suite” (in after effects).
The grading was then left as its first pass until a lot later on in the stage of production. We tend to get used to seeing an image a certain way, so it was good for us to grade it once and get used to it. This way when we came back to final grading at the end, it was as if we’d started with something that was already looking like film.
^^^Does that make sense to anyone else, or only in my head 
Anyway…
Other info???
All rendered in Vray with Physical Cameras, True Motion Blur, and True Depth of Field. (all in camera)
All the lenses used were of focal lengths that match real world lenses that would be used for racing photography. On the TrackDay we made a point of taking photos of the kind of shots we wanted in the movie, and from those could work out how much DOF we would get and how much Foreshortening would be apparent. All the cars look better foreshortened anyway, as it’s how you’re used to viewing them on TV.
So, a lot of the lenses ended up being around the 300mm to 400mm mark. We also tried to place some of the cameras in the right position on the track.
Basically just did as much as we could think of to make it look as real as possible.
I’ll try to think of some more info :wip:
Cheers,
Phil