P-51's vs. Me-109's and Fw-190's

[lesofprimus]

Not as rare as u might think... My Grandfather told me that ALL the Corsairs in his VMF were tweaked out in more ways than one.... Every extra horsepower was cherished...

Some pilots and mechanics actually used logs books for tracking the different performance changes for the different adjustments they made... Boyington liked to have his aircraft pushing as many HP as was possible...

 

[wmaxt]

Soren,

How much C3 fuel was available overall and in the field? Any fuel was an issue late in the war. Your making a lot of assumptions and passing them on as facts.

David,

I also heard of a test program at P&W that ran several 2800s at well over 3,000hp for 250 continous hours each without a failure.

wmaxt

 

[DAVIDICUS]

It was my understanding as well that such "tweaking" was commonplace.

As to that test, it was 3,600hp! The engine was a Series 57 (the engine that went into the "M" and "N" models) rated for 2,800hp at WEP.

From: http://home.att.net/~historyzone/Seversky-Republic7.html

Right out of the starting gate, the XP-47M was the horse to beat in terms of speed. The XP-47M proved to be nearly as fast as the XP-47J. 488 mph was obtained on at least one flight. The official maximum speed is 470 mph. However, over-boosting the engine could tweak another 15 to 20 mph out of the big fighter. Some may find this next tidbit hard to swallow, however, the test documents still exist.

During durability testing of the C series R-2800 by Republic, it was decided to find out at what manifold pressure and carburetor temperature caused detonation. The technicians at Republic ran the engine at extreme boost pressures that produced 3,600 hp! But wait, it gets even more amazing. They ran it at 3,600 hp for 250 hours, without any failure! This was with common 100 octane avgas. No special fuels were used. Granted, the engines were largely used up, but survived without a single component failure. Try this with Rolls Royce Merlin or Allison V-1710 and see what happens.

 

[FLYBOYJ]

Advancing the ignition timing, removing air filters, altering spark plug gap, shaving piston heads, and altering propeller tips are some of the field mods I heard mechanics did during WW2 to get more perfomance.

 

[cheddar cheese]

It was my understanding as well that such "tweaking" was commonplace.

As to that test, it was 3,600hp! The engine was a Series 57 (The engine that went into the "M" and "N" models) rated for 2,800hp at WEP.

From: http://home.att.net/~historyzone/Seversky-Republic7.html

Right out of the starting gate, the XP-47M the horse to beat in terms of speed. The XP-47M proved to be nearly as fast as the XP-47J. 488 mph was obtained on at least one flight. The official maximum speed is 470 mph. However, over-boosting the engine could tweak another 15 to 20 mph out of the big fighter. Some may find this next tidbit hard to swallow, however, the test documents still exist.

During durability testing of the C series R-2800 by Republic, it was decided to find out at what manifold pressure and carburetor temperature caused detonation. The technicians at Republic ran the engine at extreme boost pressures that produced 3,600 hp! But wait, it gets even more amazing. They ran it at 3,600 hp for 250 hours, without any failure! This was with common 100 octane avgas. No special fuels were used. Granted, the engines were largely used up, but survived without a single component failure. Try this with Rolls Royce Merlin or Allison V-1710 and see what happens.

Wow, thats pretty amazing!

 

[Soren]

Soren,

How much C3 fuel was available overall and in the field? Any fuel was an issue late in the war.

Not much, as there wasnt much fuel in the first place My point is, "It 'was' used".

Your making a lot of assumptions and passing them on as facts.

No wmaxt, im not. And plz wmaxt, lets not get judgemental here !

Not as rare as u might think... My Grandfather told me that ALL the Corsairs in his VMF were tweaked out in more ways than one.... Every extra horsepower was cherished...

And it might very well be true, however not every P-47 or Corsair had its engine tweaked.. How many did ? Who knows..

 

[DAVIDICUS]

Soren said, "And it might very well be true, however not every P-47 or Corsair had its engine tweaked.. How many did ? Who knows.."

Well, no one said every Corsair or Thunderbolt underwent such "tweaking."

Les said all the aircraft in his Grandfather's VMF were modified. Thast doesn't mean every Corsair in the theatre of operations.

I understand that such tweaking was comonplace. As for how much additional horsepower could be generated, as you said, who knows? Achieving an extra 170 horsepower (2,700hp from 2,530hp) doesn't sound so improbable as to be a rare occurence per your statement that, "It certainly wasnt impossible to tweak them that much, but it would be very rare."

Again, however, as you have said, who knows?

 

[Soren]

Well, no one said every Corsair or Thunderbolt underwent such "tweaking."

I know, I was just pointing it out.

Les said all the aircraft in his Grandfather's VMF were modified. Thast doesn't mean every Corsair in the theatre of operations.

I know, and I said that it might very well be true..

I understand that such tweaking was comonplace. As for how much additional horsepower could be generated, as you said, who knows? Achieving an extra 170 horsepower (2,700hp from 2,530hp) doesn't sound so improbable as to be a rare occurence per your statement that, "It certainly wasnt impossible to tweak them that much, but it would be very rare."

You miss-understood me.. What I meant was that this "tweaking" of P-47D's was pretty rare, except later in the war where it became abit more common.

The 170hp increase in engine-power was easely possible for a good mech, no problem there.

 

[DAVIDICUS]

Soren said, "You miss-understood me.. What I meant was that this "tweaking" of P-47D's was pretty rare, except later in the war where it became abit more common."

I think the misunderstanding was on your part. All along, I was talking about the late war "D" variant.

I said, "I remember reading somewhere on this forum that the mechanics in the field had tweaked the R-2800 engines of some late war "D" model Thunderbolts. The engines were rated at 2,530hp at WEP but were developing about 2,700 horsepower as a result."

To which you responded, "It certainly wasnt impossible to tweak them that much, but it would be very rare."

When you said "them" you were clearly referring to the late war "D" model R-2800 engines described in my post.

 

[Soren]

No you miss-undertsood me, as you thought I was implying that an 170hp increase in engine power was hard to accomplish

Btw, I hadnt noticed you wrote 'late-war' -47D's, so there I actually miss- understood you.

It goes both ways

Anyway, we do agree with each other.

 

[DAVIDICUS]

Soren said, "No you miss-undertsood me, as you thought I was implying that an 170hp increase in engine power was hard to accomplish."

Whether or not you intended to, you did imply that Soren. You said, "It certainly wasnt impossible to tweak them that much, but it would be very rare."

You said that in response to my saying, "I remember reading somewhere on this forum that the mechanics in the field had tweaked the R-2800 engines of some late war "D" model Thunderbolts. The engines were rated at 2,530hp at WEP but were developing about 2,700 horsepower as a result."

When you said, "that much" you were clearly referring to the additional 170hp represented by an increase from 2,530 to 2,700. What other reasonable meaning could you possibly have implied?

Then you, in the same response, continued with "but it would be very rare." By this, you clearly implied that while it was possible to go "that much" from 2,530 to 2,700hp, "it would be very rare." Hence, it would be possible but very rare to see "that much" of an increase in horsepower.

When I said, "It was my understanding as well that such "tweaking" was commonplace. " I was referring to the "tweaking" I had earlier referenced (which is why I set it out in in quotes) which was a tweaking resulting in a 170hp increase in the later "D" model Thunderbolt.

It was only later that you finally pointed out that "The 170hp increase in engine-power was easely possible for a good mech, no problem there."

 

[lesofprimus]

OMFG..... Someones snorting too much Ritalin.... Take a freakin qualude for christs sake...

 

[DAVIDICUS]

Hey Les, Primus Sucks. That much cannot be denied but don't sell yourself short.

You suck too.

 

[lesofprimus]

Every stinking day of my miserable life.......

Atleast u kept the reply short this time..... You really are one anal-retentive dude......

 

[Soren]

Soren said, "No you miss-undertsood me, as you thought I was implying that an 170hp increase in engine power was hard to accomplish."

Whether or not you intended to, you did imply that Soren. You said, "It certainly wasnt impossible to tweak them that much, but it would be very rare."

You said that in response to my saying, "I remember reading somewhere on this forum that the mechanics in the field had tweaked the R-2800 engines of some late war "D" model Thunderbolts. The engines were rated at 2,530hp at WEP but were developing about 2,700 horsepower as a result."

When you said, "that much" you were clearly referring to the additional 170hp represented by an increase from 2,530 to 2,700. What other reasonable meaning could you possibly have implied?

Then you, in the same response, continued with "but it would be very rare." By this, you clearly implied that while it was possible to go "that much" from 2,530 to 2,700hp, "it would be very rare." Hence, it would be possible but very rare to see "that much" of an increase in horsepower.

When I said, "It was my understanding as well that such "tweaking" was commonplace. " I was referring to the "tweaking" I had earlier referenced (which is why I set it out in in quotes) which was a tweaking resulting in a 170hp increase in the later "D" model Thunderbolt.

It was only later that you finally pointed out that "The 170hp increase in engine-power was easely possible for a good mech, no problem there."

DAVID,

What I said was "It wasnt at all impossible to tweak them that much, but it would be very rare"

Which implies it wasn't impossible, but it was rarely done... Now that it can be interpreted in two ways isn't mine or your fault.

Now shall we call it a quits, as this is rather uninteresting ?

 

[lesofprimus]

Now shall we call it a quits, as this is rather uninteresting ?

Yup...

 

[Udet]

Plan_D:

You bet the F and G versions of the Bf 109 did represent very significant improvements over every contemporary Spitfire.

Both versions could achieve things the E-3 that saw action over England during the Battle of Britain couldn´t.

The alleged story of the "critical deterioration" of the manouverability of the Bf 109, especially on the G version, does not hold water when one sees the performance of the G-6s, G-10s and G-14s that shot down both USAAF and RAF fighters in juicy quantities.

The Spitfire, in fact, was becoming a true pig by 1943, becoming heavier and heavier and less manouverable.

It appears to me there are people clinging desperately to one of the very few -if not the only one- departments where the Spitfire could "outperform" the Bf 109: turning better.

Like if turning better was the sole choice that would assure success for a fighter pilot.

Soren has made useful and illustrative arguments on how the edge slats worked on the Bf 109 apparently to no avail.

Even if you were correct when affirming the Spitfire could turn better than the Bf 109, there are still many choices left for the German pilot to find its "out" and to cleanly outfly any version of the Spitfire. It is there, in all those choices where the Bf 109 is certainly ahead of the Spitfire.

What about just one, the fuel injected DB engines on the Bf 109 against the carbureted Merlins of the Spitfire. Who could handle negative G forces better? Easy and short response: Bf 109.

By the way, the Bf 109 E-3 fared much much better during the Battle of Britain -over enemy territory- against both the MkIs -Hurricane and Spitfire- than any version of the Spitfire did over the Channel and France from 1941 to early 1943 against the Bf 109.

The Bf 109s and the Butcher Birds of JG 2 and JG 26 shot down Spitfires like flies during such period.

The Spitfire did not show any improvement in its performance against the Luftwaffe until the 8th´s Jugs began assemblying in England in 1943.

 

[FLYBOYJ]

Like if turning better was the sole choice that would assure success for a fighter pilot.

No, but I could tell you that's the second thing a pilot would look at when flying a high performance aircraft. The first is speed.

Soren has made useful and illustrative arguments on how the edge slats worked on the Bf 109 apparently to no avail.

His arguments were well taken, its a matter of how Luftwaffe pilots exploited this advantage and how RAF pilots exploited the Spits stall warning ability. I think because of this is where we got the "Spitfire could out turn a -109 acceptance," when in actuality we know that there Luftwaffe pilots who turned and out-turned Spitfires numerous times. Pilot Skill!

What about just one, the fuel injected DB engines on the Bf 109 against the carbureted Merlins of the Spitfire. Who could handle negative G forces better? Easy and short response: Bf 109.

The biggest flaw of the Spit and agree with you 100% I could not believe the Air Ministry would allow any fighter aircraft to possess this crippling characteristic.

 

[DerAdlerIstGelandet]

two cents on the topic.

I./JG 27 lost 42 K-4's during the war.
II./JG 27 lost 2 K-4's
IV./JG 27 lost 22 K-4's

Erich do you know how many of these were due to combat loss or do to other reasons?

 

[Erich]

Eagle, yes I can break all of that down, and I think Les also wanted this info. give me a bit today as I am now off work......