Gepard and nele, I did added the right engine information for the R-25-300.
See:
[Engine]
EngineName=Tumansky R-25-300 turbojet engine
SystemType=JET_ENGINE
InputName=THROTTLE_CONTROL
EngineID=1
HasAfterburner=TRUE
NumAfterburnerStages=5
SLThrustDry=48843.6 <- here
SLThrustWet=83022.0 <- and here
ThrustAngles=0.0,0.0,0.0
ThrustPosition=0.0,0.0,0.0
ThrottleRate=0.4
NozzleAnimationID=-1
IdleThrottle=0.10
IdleRPM=0.68
IdleNozzle=0.90
CruiseThrottle=0.37
CruiseRPM=0.82
CruiseNozzle=0.25
MilThrottle=0.65
MilRPM=1.00
MilNozzle=0.25
MaxThrottle=0.78
MaxRPM=1.00
MaxNozzle=0.25
FullABThrottle=1.12
FullABRPM=1.00
FullABNozzle=0.90
AltitudeTableNumData=10
AltitudeTableDeltaX=3048.0
AltitudeTableStartX=0.0
AltitudeTableData=1.000,0.790,0.636,0.526,0.446,0.406,0.359,0.339,0.000,0.000
DryMachTableNumData=4
DryMachTableDeltaX=0.4
DryMachTableStartX=0.0
DryMachTableData=1.000,0.980,1.172,0.000
WetMachTableNumData=7
WetMachTableDeltaX=0.4
WetMachTableStartX=0.0
WetMachTableData=1.000,0.991,1.207,1.683,2.473,2.750,3.027
TSFCM0=0.961
TSFCM1=1.360
AfterburnerTSFC=2.157
MinFuelFlow=0.01
ExhaustEmitterName=CleanExhaustEmitter
ExhaustPosition=0.0,-6.00,0.00
AfterburnerEmitterName=AfterburnerEmitter2
FireSuppression=TRUE
MinExtentPosition=-0.55,-6.90,-0.55
MaxExtentPosition= 0.55,-2.10, 0.55
and other stuff