Ki-43-II 'Oscar 2' performance differences

[Laurelix]

Ki-43's had different Nose designs...

As you may recall... A6M3 Clipped with 1130hp engine achieved 545km/h at 6000m
A6M5 had same wing area and the same engine and intially achieved also 545km/h at 6000m max speed.
The first 200 A6M5's didnt get the individual exghaust pipes for each cylinder which had pipes aimed backwards which created a rocket effect increasing the max speed to 565km/h at 6000m and also improving the climb rate from 7:27 to 6000m to 7:01 to 6000m.

Im not sure if this is correct but... from what i was able to gather...

KI-43-II Prototypes with the initial type nose achieved 515km/h at 6000m at military power
Ki-43-IIa with the early type nose also achieved 515km/h at 6000m at military power
Ki-43-IIb with the late type nose achieved (515< X km/h < 535) at 6000m at military power
Ki-43-II Kai with the final type nose achieved 535km/h at 6000m at military power
Ki-43-III Ko with its new type nose achieved 560km/h at 5850m at military power

 

[Laurelix]

So the first A6M5 Mod 52's actually did not have exhausts for individual cylinder. It was identical nose design to the A6M3 series.
It was only capable of 545km/h at 6k metres altitude and it took 7:27 to climb to 6000m. So the same top speed as Clipped A6M3 but worse climb rate and worse turn rate.

Eventually the Japanese gave the A6M5, a exhaust pipe to each cylinder and it was aimed towards the back creating a 'rocket effect'
This version of the A6M5 was finally capable of 565km/h at 6000m / 7:01 to 6000m rate of climb

 

[taly01]

I have found no photo evidence that production Ki-43-II kai had lower exiting exhausts like A6M5, all the pictures show them in similar areas to Ki-43-III.

The early A6M5 with multiple exhausts pipes burned its tyres as the lowest exhaust exit was close to the retracted wheels cover. They soon shortened the lowest exhaust so it exited earlier into the air stream, cooling the gases a bit before it came near the retracted tyres area.

It is for this reason I believe the final model 2 Ki-43 (kai or -c, 548kph Gakken) never had lower exiting exhaust pipes, although some book drawings show them as in your picture above. The Ki43 had no tyre door covers so could burn tyres worse than A6M ! I think wrecked Ki-84 were the source of the incorrect Ki-43-II kai exhaust drawings. some even show 4 centre pipes like Ki-84! Also Ki-84 wingtip shape sometimes appears on Ki-43 drawings. The Ki-84 wingtip is more "forward" curved, while Ki-43 is a bit more evenly curved. Wrecked parts of Ki-84 and Ki-43 can be confusing to tell apart!

 

[Laurelix]

I have found no photo evidence that production Ki-43-II kai had lower exiting exhausts like A6M5, all the pictures show them in similar areas to Ki-43-III.

The early A6M5 with multiple exhausts pipes burned its tyres as the lowest exhaust exit was close to the retracted wheels cover. They soon shortened the lowest exhaust so it exited earlier into the air stream, cooling the gases a bit before it came near the retracted tyres area.

It is for this reason I believe the final model 2 Ki-43 (kai or -c, 548kph Gakken) never had lower exiting exhaust pipes, although some book drawings show them as in your picture above. The Ki43 had no tyre door covers so could burn tyres worse than A6M ! I think wrecked Ki-84 were the source of the incorrect Ki-43-II kai exhaust drawings. some even show 4 centre pipes like Ki-84! Also Ki-84 wingtip shape sometimes appears on Ki-43 drawings. The Ki-84 wingtip is more "forward" curved, while Ki-43 is a bit more evenly curved. Wrecked parts of Ki-84 and Ki-43 can be confusing to tell apart!

This is the Ki-43-II Kai

 

[taly01]

Yes I think that is the "normal" Ki43-II kai exhaust arrangement, from actual photos,

yet there are quite a few book drawings not like that ?!

My theory is they confused with Ki-84.