Looks like you are filling your weekends pretty well. For some midweek Banger/Stock Car racing I do recommend Wednesday nights at Arlington Stadium, near Eastbourne. Great track to watch from, you are right up close to the action.
Fixtures here
http://www.spedeworth.co.uk/venue.php?name=Eastbourne
The Legends on the 19th June are usually good and the Classic Hot Rods and Heritage cars on 3rd July are well worth a look, Bangers are pretty much on every week too for a bit of bash/crash...