I wasn't quite sure where to post this video by Guy Martin.
Anyone who's seen Guy on TV will be aware that he's never happy with things at 'stock' settings. For him it has to be faster, more powerful, noisier and more dangerous.
Here, he's bought himself a worknig RR Merlin engine. Not happy with the revs limited to 1800 RPM he's meddled with the rev limiter and pushed it to 2800 RPM. His description of the mayhem that ensued is hilarious.
Although much damage was done, no one was hurt and the RR Merlin seems to have survived.