Yes basically the 190D9 engine the Jumo 213A-1 liquid cooled 12 cylinder in-line engine is rated at 1,776HP for take off.With MW50 water methanol injection the engine rates 2,240HP.
this is from 'The luftwaffe fighter force: the view from the cockpit' Adolf galland et al edited by david C Isby and all info is taken from 'Air defence of the reich volume 2 the fighter arm (the jagdwaffe) Pamphlet series september 1944'
this is part of a training sect.Nr 1410/44 confidential report for trainees in 44.....
'Another method of raising engine performance is by water-methanol injection.This helps to cool the engine and brings about an incresed performance by greater manifold pressure.Methanol has a favourable influence on anti-knock properties.The increase in power is greatest at low altitudes.It has an increase of about 30 km/hour at all altitudes up to
full boost altitudes(where the engine had its best performance).Used in periods of 2-20 minutes.'
so here you have an explanation. What it basically means is the p51 would run his engine at max boost until it overheated where as the water metanol actually PROTECTED the engine from damage while it was used.Also according to this book it ran for
20 minutes so again the dora has half what it had in real life.
I knew this before and have accepted the 10 minutes in AH as a 'representation' of the real times just as im sure the p51d runs at full manifold(wep) for more than 5 minutes right? Lets hope so eh? or we may have uncovered yet another strange discrepency.
So
John9001 when you say "so when your dora ran out of "boost fuel ' the P51 would catch you and shoot you down as they did in real life." lets think about it for a second.You run full boost for too long you cause more damage to the engine than the dora would and the dora would STILL have normal wep after the methonol ran out.so the dora could go full boost for something like 20 minutes with methanol while you boost to top temp in half that time in p51 then probably after the water methanol is switched off the dora could then run quite a while without the water methanol and ignore the wear and tear to the engine (if hes chased) whereas your P51 by this time is rattling its pistons and melting! catch them at the end of a fight in your 51 and yes you would run them down but so would a dora that catches your overheated p51 if the situation was reversed

maybe this explains that report by kurt tank about how he opened the throttle on a ta152 and left 2 diving p51s behind? We all suspect its just idle boasting but then again who knows?

anyway back to the subject:
Dora should have 10 mins boost and then cool at the same rate as any other liquid cooled aircraft.The top temp is around 120 to 130 on all planes in AH's simplified wep so they should cool down in the same time. I really cant see any justification so far which explains the present system of 2X the wait for the dora.