Stock Cars...in the pits

I've been following stock cars for many years and am in Kings Lynn for one of the semi-finals of the World Championships.
Stock cars have evolved since the early days of crash bang wallop. A good car now costs £30,000 and the big V8 engines give 600+ horse power.
Tracks can be either shale or tarmac and some of the best drivers have different cars for each racing surface.
The whole thing is organised by BRISCA [www.brisca.com].
The big differences with other forms of motor sport are that contact between cars is allowed, and at most meetings the best drivers start at the back of the grid, so the excitement is to see them try to overtake the rest of the field to get to the front as the race progresses.
Here endeth the lesson!