Since the lotus and the lancia have pretty much straight through pipes, do the French turn a deaf ear or do they fine for it? If they do.. Than, oh well not going to change it any more...
mine was measured at Castle Coombe at 106dB and never had any bother en route or whilst at Le Mans...don't draw attention to yourself and you will be just fine.
Can't speak for the gendarmes, but in general the French are much more excitable about noisy sports cars than just about any other nation, ours included.
We have been in France for just over a week and are heading to Le Mans at the end of this week. We are in a 108 dB Vanquish and have had only appreciative looks even when launch controlled out of Peage gates!