Originally posted by Squire
The Spitfire IX carbs on the Merlin 61 and 63 were not fuel injected, but they were "negative-g" float carbs. The Spit F.IX did not suffer from neg-g cutout. No version of the Spit IX (or later varients) did.
" It would have been easier for the Spitfire IX to follow the Fw190 in a diving turn if its engine had been fitted with a negative 'G' carburettor, as this type of of engine with the ordinary carburettor cuts very easily."
[Spitfire IX-Fw190 tactical trials, Alfred Price: Fighter Aircraft]
" The problem of engine cutting under negative g had also been a great disadvantage in combat. The excellent Miss Schilling at the RAE, Farnborough, had already achieved a substantial amelioration of this problem but no means a full solution. I had no idea what the final answer would be but was sure I should press very hard it to be found ( It was, with the Bendix Stromberg carburettor, but it took a long time)."
[ Jeffrey Quill: Spitfire]