I can't speak for the Mod but I found references when researching the Ta152C variants.
In a story telling format, it starts with some problems with the Jumo 213's gear functions in the third stage for high altitude operation. Most of the time in practise you were lucky to get the second auto supercharger gear, pressures were all over the place at high alt. It'd kick up and kick back and altogether wasn't very reliable above something like 8000 metres (only Kurt Tank himself managed to get a Ta152H anywhere near its claimed maximum alt and service maximum was restricted to 10500 metres for other reasons, point being it didn't return the predicted performance curves claimed by Focke Wulf and this was a little embarressing for the RLM...don't get me wrong at 7-8000m the 213E was brilliant and virtually unbeatable but sometimes higher than that it'd just keep kicking the blower into lower gears and run out of puff).
In fact general reliability issues with the 213E were such that Focke Wulf and Luftwaffe field personnel couldn't even agree on idle settings.
The story goes Kurt Tank had predicted these shortcomings since early 1943 and had always promoted use of the DB603 in preference over the Jumo. Essentially the Daimler uses a dirty big supercharger casing with a dual stage, huge swept capacity and cheats with the hydraulic spooling. Higher altitude operation is the bread and butter of Daimlers, it's at low alt they're a compromise but still do okay using sheer torque (with a high oil temp because of all the slippage in the blower drive).
The Daimler is like a truck engine. Simpler but far less to go wrong with and it just lapped up gulping large volumes of low density air and turning it into pressurised horsepower. Where a Jumo 213E is brilliant at 7-8000 metres, the DB603L is brilliant at 9-10000 metres. In fact above 5000 metres it eats Jumos for breakfast, but at lower altitudes the Jumo is faster. Mechanical versus hydraulic blower gearing, bound to get lag (fyi most calculated performance curves for Daimlers do not compensate for the blower lag they had, there's a big flat spot at mid range in all Daimlers, a DB605 for example loses a ton of power at about 3000 metres iirc).
Now we talk about the FW-190D which started as an interim but evolved into its own fighter type by 1944 (preproduction testbeds were delivered mid 1943). The RLM was still stuck on the Jumo because conceptually it was very impressive. Even at this stage however the rushed 213A performance was subpar and various boost methods were being investigated (adapted one from the BMW engine, tried the Messerschmitt one, developed a new one), all the while Tank was still saying the Daimler was better.
Now the Dora was meant to evolve into both single stage low-med and two stage high alt variants (the latter more of a Ta152 interim, the former more a 190A-8/9 replacement on existing production lines), but even so much heavier Ta152C preproduction prototypes fitted with the single stage 603E engine were effortlessly cracking 610km/h and 2300PS at sea level by November 1944.
So Kurt Tank put a DB603 into a Fw190D and it cracked 730km/h over the airfield. Plans were already in motion for the D-11/13 series but finally the RLM turned around and cast the D-14/15 to replace them before production even begun and even to replace the Jumo 213E in the Ta152H to a Daimler. This meant the way things take time, there would be short production runs of Jumo engine versions of both aircraft and through the course of 1945, probably in the second half both would transition to the Daimler during production.
To answer your question more directly, it depends on which engine fitted. D14 was to be 603E or LA, D15 use the 603EB or G. 190D with 603G is about the same up to 5500m and is much faster higher than that, with a throttle altitude 1500 metres higher than the single stage Jumo. Other variants have different characteristics.
The Jumo and Daimler are just completely different animals.
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Topic: DB603-Dora (Read 62656 times)
