Sounds like you will be running with the big boys on the 18th then mate
. It's the complete other end of the scale to my old Golf. In fact my Ed30 was more related to your A8 by the sounds of things.
I use to do 30k a year in it for work (Sales Manager) and then take it to the odd event like this and Pod without changing a thing (maybe the odd bottle of octane booster here and there for what difference that made if any). It was my daily that would take me round the UK Monday to Friday kicking out 36+mpg, but still do a 12.7 @ 114mph at Pod at the weekends with minimal mods (intake, Exhaust, map and fuel pump) and without doing a thing to it.. That's why I miss it so much from time to time, ticked all the boxes for me. The BM does the same job, just not such a sleeper.
Would love a proper track weapon/project at some point though. It's just knowing where to stop..