What is the legal limit on car exhaust noise?

When my neighbour fires up his Porsche, it sounds as though an explosion has taken place. Is this noise standard or can it be 'tweaked' in some way? Is there a legal limit to the noise that cars can produce?

Asked on 30 September 2020 by W J Stevenson

Answered by Andrew Brady
Porsches can be pretty noisy on start-up. The legal limit is 74 decibels. It won't be more than this unless your neighbour has modified it to make it noisier. It might be worth a civil conversation in the first instance. He might not realise how noisy his car is on the outside, for example, so perhaps could park further away or try to avoid starting it during unsociable hours.
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