Compare some late -post WW II fighter

[mig-31bm]

The speed graph for the P-51H from the test you've posted was done on 61 and 67 in Hg of manifold pressure (MAP). That means that ADI )water-methanol mixture) was not used. With ADI, the engine was capable for 90 in Hg of manifold pressure. More MAP = more HP = greater speed. On the other hand, some tests clearly state that, even with 90 in Hg, the P-51H was capable for only 450 mph.
You can find several tests of the P-51H here (scroll down a bit). Some data about maneuverability (not just that) can be found here.

Edit : sorry just checked again , yeah there was a table for P-51H

 

[mig-31bm]

btw why the P-51H with 61 and 67 in Hg an reach higher altitude than the one with 90 in Hg ( as seen in the graph ) ,also what the different between an interceptor version of P-51H and a normal one ? it seem quite a bit lighter ( or the interceptor only mean less fuel ?)

 

[Aozora]

btw why the P-51H with 61 and 67 in Hg an reach higher altitude than the one with 90 in Hg ( as seen in the graph ) ,also what the different between an interceptor version of P-51H and a normal one ? it seem quite a bit lighter ( or the interceptor only mean less fuel ?)

The altitude measurement represent the heights to which the P-51H 44-64-182 was flown to accomplish the tests at various power settings - in this case 36,000 ft because:

J. High Altitude Trials.

Under test conditions, the pilot determined 36,000 ft. to be the maximum practical condition for cruising. At this altitude three satisfactory level flight points using 3000, 2700 and 2500 rpm were obtained. Above 36,000 ft. the maximum level flight indicated airspeed at normal rated rpm begins decreasing rapidly with altitude.

 

[wuzak]

btw why the P-51H with 61 and 67 in Hg an reach higher altitude than the one with 90 in Hg ( as seen in the graph ) ,also what the different between an interceptor version of P-51H and a normal one ? it seem quite a bit lighter ( or the interceptor only mean less fuel ?)

It is limited by the supercharger.

As the aircraft gains altitude the pressure ratio required to maintain a given boost level also rises. But the pressure ratio is governed by the supercharger design and the speed at which it is run - which explains why many superchargers used multiple or variable speeds.

A supercharger will have a critical altitude or full throttle height. This is the highest altitude at which the supercharger can deliver a given boost pressure. Below that altitude the supercharger can deliver more boost, and so the engine is throttled to prevent too much boost being delivered. Above that altitude, however, teh supercharger is unable to maintain the boost and mass air flow.

As the supercharger is capable of higher boosts at lower altitudes extra power can be obtained provided the engine is capable of taking the extra pressures involved and there are no issues with combustion. That is why fuels with higher octane (or performance number, PN) were developed, as well as ADI.

To gain the higher boost at higher altitudes requires a redesign of the supercharger.

 

[spicmart]

Was the Fw 190D-13 able to keep up with the Allied superprops ( (Sea Fury, Spiteful, Bearcat, Super Corsair, P-51H), XP-47/72 ) or would it have needed the Jumo 213EB or later to do so?

 

[davparlr]

Was the Fw 190D-13 able to keep up with the Allied superprops ( (Sea Fury, Spiteful, Bearcat, Super Corsair, P-51H), XP-47/72 ) or would it have needed the Jumo 213EB or later to do so?

Couldn't find much on the -13. With the F engine it would probably be comparable to the P-51D and Spitfire XIV, et.al. With the EB it would probably be comparable to the P-51H and latest Spitfires but it would have trouble between 25k and 35k with the P-47M/N. The XP-72 was such an awesome aircraft with 3500 hp (about the same as the Do 335 with both engines) few prop planes would be able to keep up with it.

 

[spicmart]

Couldn't find much on the -13. With the F engine it would probably be comparable to the P-51D and Spitfire XIV, et.al. With the EB it would probably be comparable to the P-51H and latest Spitfires but it would have trouble between 25k and 35k with the P-47M/N. The XP-72 was such an awesome aircraft with 3500 hp (about the same as the Do 335 with both engines) few prop planes would be able to keep up with it.

Dora-9 with Jumo213A was the equal of P-51B/D and Spitfire Mk XIV but not at altitudes. Jumo 213E/ gave the Doras/Ta 152s parity. Very up high they were even better and able to fight aganst the P-47.
The Jumo213J gave 2900 PS with MW50 (imagine it got 130/150 grade fuel). With this engine the Focke Wulf fighters should be at able to catch up with the XP-72 etc.. Less power but better streamlining/smaller and lighter airframe than the German planes.