Hey Kuffie!
"From what I have seen, the Mk VIII falls short of these speed and climb data you claim for it, esp. trop ones. It has the exactsame engine as the MkIX, and is heavier... why would it climb faster, or even as fast ? All data I have seen show almost the same speed as the IXs, ie. 400ish top speed. THe FW 190A-5 from what I have seen was somewhat faster at altitudee, quite faster at low alts, and of course climbed quite a bit worser (being a much heavier plane with smaller wings), ie. 3800-4000, whereas IXs climbed 4650, and the VIIIs were probably worser, being 300lbs heavier.."
I have just the data from testing as well as some info from the far east.
(5000 fpm and 420 mph)
It got "cleaned up" some bit as well as many "other improvements" (J.Quill),- what exactly he refers to I am not sure about. Internal bullet proof glass on the windscreen and a retractable tailwheel come to my mind there. (I know about the tailwheel but need data on the other)
As for the Engine, it would be the Merlin 66 or 70, - our AH Merlin being the early 61.
The 190 should be faster at lower alt, and slower at high alt, - the Merlin 66 and 70 peaking out rather high. The 190 will be better downhill, - but alas, - downhill is an attempt to disengage. Running.
Uphill will count as somewhat more important IMHO.
So. - I'm off to bed.
Cheers.