Salute
Kudos to the OP for the effort he has put in to maximize performance from the Spitfire, he should get every credit.
Unfortunately, the fact is, this still does not change anything in regards to the complete failure of the game to properly model both the Hurricane and Spitfire.
The Spitfire 1A 100 octane is still 44 mph too slow, and climbs much worse than the actual aircraft.
It was capable of running for 5 minutes at +12/3000 rpm, and considerably longer at lower rpms, something which it is incapable of now.
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The Hurricane has the same problems, too slow, climbs poorly compared with historical, and overheats much too soon at lower rpms.