DB vs Merlin vs ?? (1 Viewer)

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It's interesting to look at what they were getting out of the late two-stage blower V-1710's. A rare engine, only used in the P-51H, some P-82 Twin Mustangs, and the P-63. I don't have the figures in front of me, but they were quite a bit more powerful. There was also a V-3420, 24 cylinder double-V Allison, developed for a B-29 version (B-39?). I think it was real close to 3000 h.p.. What about the Junkers Jumo?
 
V-1710 said:
It's interesting to look at what they were getting out of the late two-stage blower V-1710's. A rare engine, only used in the P-51H, some P-82 Twin Mustangs, and the P-63. I don't have the figures in front of me, but they were quite a bit more powerful. There was also a V-3420, 24 cylinder double-V Allison, developed for a B-29 version (B-39?). I think it was real close to 3000 h.p.. What about the Junkers Jumo?

The P-51H used a Packard Merlin V-1650-9 engine, not an Allison V-1710. The earlier models of the F-82 also used Merlins, and were generally 15-20 mph faster than Allison engined variants.
 
My mistake, it was the P-51J that had the 2 stage Allison. I think only 2 were built, and they had about 2,300 h.p.. The idea was that because Packard was going to have to start paying royalties to Rolls-Royce to continue Merlin production after the war's end, thought was given to going back to the Allison on the P-51.
 
V-1710 said:
My mistake, it was the P-51J that had the 2 stage Allison. I think only 2 were built, and they had about 2,300 h.p.. The idea was that because Packard was going to have to start paying royalties to Rolls-Royce to continue Merlin production after the war's end, thought was given to going back to the Allison on the P-51.

The P-51J used an Allison V-1710-119, rated at 1720 max output, not 2,300 hp.

From Joe Baughers excellent website;

"The last prototype in the lightweight NA-105 series was the XP-51J, which was similar to the F and G models except that it reintroduced the Allison V-1710 engine to bring the Mustang full circle. The Allison engine was, however, the V-1710-119 version with a two stage, gear-driven supercharger, rated at 1500 hp for takeoff and 1720 hp with water injection at 20,700 feet. Unlike earlier Allisons, this engine had an updraft carburetor. The nose geometry was substantially modified, and all air inlets in the nose were completely eliminated. Instead, the carburetor air was taken in through a ram inlet at the front of the radiator duct and piped to the engine. A dorsal fin was fitted.

Two XP-51J prototypes were ordered, with serial numbers being 44-76027 and 44-76028. 44-76027 made its first flight on April 23, 1945, piloted by Joe Barton. The XP-51J weighed 6030 pounds empty and 7550 pounds normal loaded. It was anticipated that a maximum speed of 491 mph could be achieved at an altitude of 27,400 feet, but this was never achieved during tests because the new Allison had not yet been cleared for full power operations. XP-51J Ser No 44-76027 was, in fact, loaned to Allison so that they could use it to iron out the bugs in their engine. The other XP-51J prototype, Ser No 44-76028, was never actually flown, but was scavenged for spare parts to keep the other example flying. The end of the war in the Pacific brought all further work on the XP-51J to an end. "
 
I have one source that lists the V-1710-119 as having 2,300 h.p., but other sources say 1720 h.p., as you pointed out. Maybe the higher figure was a proposed output, or a WER, but I now think the 1720 figure may indeed be more accurate.
 
schwarzpanzer said:
Great info there helmitsmit. :)

I've often wondered why Rolls-Royce didn't use sleeve valves, before BMW bought 'em that is. :rolleyes:

Never heard of the R-R Eagle 22, Pennine and Crecy in development in the early 40s then.

Eagle

http://www.enginehistory.org/eagle_22.htm

H24 sleeve valve
2238ci
5.4" x 5.125" (b x s)
3500hp@3500rpm
2 stage, 2 speed intercooled, aftercooled(1/bank) supercharging

Was to be used in the Wyvern.

Pennine

X24 sleeve valve aircooled
2685ci
5.4" x 5.0" (b x s)
3000hp potential

Crecy

V-12 90* sleeve valve 2 stroke
1593ci
5.1" x 6.5" (b x s)
37" (104" Hg) boost with ADI > 3.6hp/ci


Oh yes forgot, the BMW801 was putting out 2200hp+ with the F model.
 
Cylinder-for-cylinder, the VW Beetle boxer engine seems a lot better than the DB iverted vee's.

Who else thinks a 12 cylinder version would've been good?
 
As in a 12-cylinder boxer? Well they are very flat and low, which would have given it a low frontal area and lower center of gravity...It would have been interesting.
 
V-1710 said:
I have one source that lists the V-1710-119 as having 2,300 h.p., but other sources say 1720 h.p., as you pointed out. Maybe the higher figure was a proposed output, or a WER, but I now think the 1720 figure may indeed be more accurate.

The 2,300hp was in a test cell @ 90" boost.
The F-30 series 111/113 engines were given a 1,725hp @ 64" service rating by field order for WEP service.
The G6R-143 model used in the P-82s was rated @ 2,250hp at 3,200rpm.
The prototype engine for the P-63Q was rated @ 2,900hp but was not put into service for several reasons.

wmaxt
 
FLYBOYJ said:
Jabiru makes an 8 cylinder opposed, Kloeckner-Humboldt-Deutz made a 16 cylinder opposed diesel engine during WW2. Franklin and Continental also made 8 cylinder opposed engines, Frankin did do a 12...

http://www.jabiru.net.au/engines/8cylinder/

There is also 'flat' Junkers diesel engines.

Jumo 2xx series, 6 cylinders, 12 pistons

http://www.geocities.com/hjunkers/ju_jumo205_a1.htm used in the Dornier Do 18, Dornier Do 24, Dornier Do 26, Blohm Voss BV138

http://www.geocities.com/hjunkers/
 
I believe the only H-block engines were the Napier Sabre and the Rolls-Royce Eagle 22.

The Eagle was basiclly two flat 12 engines, one on top of the other, running a common crank. It produced 3,550 HP from 2,817 cubic inches, or 2,647 kW from 46.2 liters.

Bore was 5.40 inches, stroke was 5.125 inches (13.72 cm x 13.02 cm).
 

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