Just looking through some trackday stuff and Focused Events have got a quiet day on August 4th for £99! I assume the Duc could pass the noise limit with a DB killer in?
There are noisy days near to the race meeting, but they're around £50 more. There's a quiet day Saturday 12th, before the meeting too, but that's £135.
Anyone up for the cheap day....not that I'm tight or owt