Dogwalker
Senior Airman
Ok, let's see.True but that is problem when you take a 1920s engine and put a reduction gear on the front and supercharger on the back and keep all the old stuff inbetween.
OK 2nd rate engine
You have a 32.65 liter engine turning at 2350rpm (at best?) and the DB 601 is 33.9 and turning 2400rpm and 2500rpm for take-off.
BoreXstroke:
Asso XI 146x160
DB 601 150x160
RPM:
Asso XI RC.40
"normal": 2250 rpm
maximum: 2400 rpm, without time limit listed in the manual
"exceptional": 2590 rpm, for 30"
DB601 A-1
"normal": 2200 rpm.
("military"?): 2300 rpm for 30'
maximum: 2400 rpm for 5'
takeoff only: 2400 rpm (with more boost) for 1'.
They seem pretty comparable.
The real difference,apart for the slight difference in displacement, seems to be the supercharger rating. The Asso XI was a sea-level atmospheric pressure engine. At 2400rpm at 4000m it produced 900ps with 860mmHg/1.13atm pressure provided by the supercharger (and "normal" power, at 2250rpm, at 4000m was with 822mmHg/1.08atm). The DB601A-1 was slightly supercharged. At 2400rpm at 4000m it developed 1020ps with 1.30atm (for 5'). At takeoff the it could use 1.4atm for 1'.
I don't have the manual for the Asso L.121 , but it seems very likely they increased the pressure for that too, since it mantained the same bore and stroke and fuel of the Asso XI and rised 60hp power. It doesn't seem credible they further increased the rpm, when the Asso could already rev faster than the DB601.
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