Spit IIa is now so much more inferior to the 109

[Kwiatek]

Originally Posted by Kurfürst

Spitfire Mark II was not cleared for +12 lbs boost during the Battle of Britain, apart for takeoff. For combat flying at all but the lowest altitudes, +9 lbs was allowed, with 100 octane fuel.

So the current +9 lbs performance is correct, regardless of fuel type.

Not exacly correct beacuse there is not possible to apply +12 lbs in Clod SPit II even only at take off up to 1000 ft (300m) or 3 minutes rating like manual clamied. So still not accurate even for 100 Octan fuel modeling.