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Let me guess: author of the video is Greg?I watched a video on youtube, the author explained that, even though BF-109 is lighter and has bigger engine than P-51, the P-51 ended up being much faster because USA has fuel with much better octane rating of upto 150 while German fuel octance rating is around 80-100.
You got it.Would they get a huge boost in performance? Or their engine can't handle it?
The DB 605 engine was about the same weight as the engine in the P-51.I watched a video on youtube, the author explained that, even though BF-109 is lighter and has bigger engine than P-51, the P-51 ended up being much faster because USA has fuel with much better octane rating of upto 150 while German fuel octance rating is around 80-100.
What kind of German fuel?A Griffon running on the German fuel would be carrying around about 90kgs of extra weight that it couldn't use because of the fuel.
Ah yes indeed, it greg, he seem to know a lot about ww ii aircraft i thinkLet me guess: author of the video is Greg?
Problem with him is twofold the way I see it:Ah yes indeed, it greg, he seem to know a lot about ww ii aircraft i think
View: https://youtu.be/OqiG9VHuBbM?si=w7ZY3U19tfUEXC54
1947 Sweden was making DB 605 engines to put in Saab 19 bombers and Saab 21 fighters. They were supposed to have used 91/96 octane fuel in them. They got 1575hp at 7000ft from them and 1475hp at take-off using 6.3lbs of boost.
BMEP was 203psi at 1575hp.
Sweden was building the Saab 90 airliner at this time using P&W R-2000 engines and planning on using R-2180 engines, both using 100/130 fuel. The R-2000 had a BMEP of 211. They could get 100/130 fuel in 1946/47.
A Merlin V-1650-9 running at 1520hp at 14,400ft was running at 243 BMEP on 100/130 fuel. They could make a lot more power using different fuel using more boost and higher BMEP.
But if you simply pour in the better fuel and crank up the boost limiter on the DB 605 you are going to break connecting rods, pistons, crankshafts and possible lift the cylinders/head assemblies off the crankcase.
It wasn't just the fuel the Mustang was using, the P-51 was aerodynamically superior to any piston engine German fighter that saw service.I watched a video on youtube, the author explained that, even though BF-109 is lighter and has bigger engine than P-51, the P-51 ended up being much faster because USA has fuel with much better octane rating of upto 150 while German fuel octance rating is around 80-100.
So my question is, what would happen if we give FW-190, Ta-152 150 octane fuel ? Would they get a huge boost in performance? Or their engine can't handle it?
Thank you for the correction.Some of this is correct, but your words about the DB 605 are not completely correct. The Swedish DB 605 was operated on Flygbensin 100/130 and they did indeed just "crank up the boost limiter on the DB 605". There was an option of the original 1.42ata limit or an increased 1.65ata limit that gave an increase of 15% power at altitudes up to around 10,000'.
However, all engines do require to be built to match their operating loads and demands so, there are limits if you do not improve the design when increasing the boost loading, or
you will suffer increased wear and tear on the engine. So, just as the various versions of Merlin engines were able to operate on different fuel at different boost levels and power ratings, so could different versions of the the DB 605.
Eng
Thank you for the correction.
But it does show that 100/130 fuel would not give the amount of improvement than many people think.
Years ago I'read somewhere that DB 605 ASC was able to do 1.98ata MAP even with their bad late-war C3 fuel (max. 98 octane or so). Apparently in March 1945 there were some converted Bf 109 G and K at eastern theatre. And also, that on factory dynos DB 605s were running well above 2.0ata. Sounds like with good fuel this engine would had further potential.You are correct that it is not just a matter of using a higher Octane fuel in an engine designed for lower Octane. In the case of the DB 605 A there was obviously the capability on engines built after about Autumn 1943 to have been uprated to about 1.65ata MAP using 100/130. However, the Germans did not take this option until the later introduction of MW50, in early Summer 1944, when they linked that with the mandatory use of C3 fuel to give an emergency limit of 1.7ata MAP for a relatively long-duration 10min period, with 5min recovery between use.
It is interesting to consider the results that Rolls-Royce achieved on the smaller late-war Merlin compared to DB with their late DB 605. Using 100/130, RR achieved rating at 18lb boost. Whereas, using a similar late C3 fuel, DB achieved rating (without MW) at 1.8ata MAP (11.76lb boost).
Eng
Hi.Years ago I'read somewhere that DB 605 ASC was able to do 1.98ata MAP even with their bad late-war C3 fuel (max. 98 octane or so). Apparently in March 1945 there were some converted Bf 109 G and K at eastern theatre. And also, that on factory dynos DB 605s were running well above 2.0ata. Sounds like with good fuel this engine would had further potential.
Edit: found this one, is it known?
Olivier was active on his Bf 109 info site for around 10 years, and the site still seems available.Kurfürst is some kind of controversial luminary wrt the Me 109 iirc. Has he ever published articles or books?
I've heard of this too. Would anyone have a source for it?And also, that on factory dynos DB 605s were running well above 2.0ata.
There is a story that one P&W engineer ran a R-2800 at well over 100in on a factory dyno. Over 3.0 ata. He was in the next test cell to some guys working on the R-4360 (28 cylinder engine) and he was trying to beat them. He was using enormous amounts of water/alcohol. It was only for a few seconds. The engine survived (as supposed to have been a "B" series engine and not one of the later "C"s.And also, that on factory dynos DB 605s were running well above 2.0ata. Sounds like with good fuel this engine would had further potential.
Yes, PFF 44-1 is 100/150 grade.44-1 fuel (100/150?)