Look up Sqd Ldr Martindale, I think from Boscombe Down but I’m not certain. He, and a Spitfire, had a very high speed dive which resulted in the entire reduction gear and prop being torn off. Amazingly, I seem to recall he landed the battered remains.

The other one to look up is Flt Lt Ted Powles who I believe is recorded as having the highest verified speed in a Spitfire from a very high altitude over Hong Kong.

Apart from confirming Powles’ name this is all from memory so don’t believe a word until you’ve checked!