Mikoyan-Gurevich MiG-3 with AM-38 engine

Due to the clumsiness of the MiG-3 at low altittudes, where most of the aerial combat took place, it was decided to test the AM-38F engine on the fuselage of a MiG-3. It was rated at 1600hp and flew for the first time on 31st July 1941. Testing was prolonged for 12 days and were performed by test pilot Y.K. Stankevich and chief engineer K.N. Mkrtychan. Thanks to the additional power, the performance at low altittude got better, below the 4000m high.
It was tested in two configurations: The original one made by Zavod (factory) Nº1 in Moscow and a second one with some minor modifications proposed by the chief engineer like a new design of the exhaust stack fairings, bomb shackles removed and inert gas system was installed. With the first configuration, the original one, achieved a respectable speed of 582km/h (361,64mph) the second one achieved a better speed of 592km/h (367.85mph). The AM-38F engine could easily replace the original AM-35A without any radical changes to the fuselage, however, the cooling system proved to be insufficient for this more powerful engine, as it couldn't operate in a satisfactory when temperature on the ground was above 16ºC (60.80F). After being tested at Nil test centre, it returned to Zavod Nº1 to fix that cooling problem, but after some of those fixings, the supercharger started to be troublesome and during a test flight, the fuel tanks were deformed due to it. Twenty-two flights were performed and on 22nd September it returned again to Zavod Nº1 to be repaired. On 4th October 1941 it flew again on the airstrip of the Zavod Nº1, but on the next it crashed killing the test pilot, N.P. Baulin, however, later investigations proved that it was shot down by a German aircraft.
Given the shortage of AM-35A engines, some units operated on their own with the AM-38F engine. In fact, two aircrafts of the 402nd IAP were fitted with it in November 1941 and were tested by the regimental Commander Major K.A. Grudzev and the Squadron Commander B.G. Boroday who managed to shot down two enemy bombers while testing it.
The fate of those modified fighters, however, is unknown.

Sources:
1. http://www.airpages.ru/eng/ru/mig3_2.shtml
2.https://en.wikipedia.org/wiki/Mikoyan-Gurevich_MiG-3
3. https://ru.wikipedia.org/wiki/МиГ-3 (translated)
4. Salamander Books - The Complete Book of Fighters
5. Signal Squadron - Aircraft In action 204 - Early Mig Fighters in Action