This is an example of how engines and gear ratios are modelized in this car simulator.

Proton_engine.ini


// Engine data generated by PhysicsEditor
RPMTorque=( 0.0, -13.9, 0.0)
RPMTorque=( 500.0, -22.5, 76.1)
RPMTorque=( 1000.0, -32.4, 149.7)
RPMTorque=( 1500.0, -43.3, 230.0)
RPMTorque=( 2000.0, -54.9, 308.7)
RPMTorque=( 2500.0, -66.9, 394.0)
RPMTorque=( 3000.0, -79.2, 482.7)
RPMTorque=( 3500.0, -91.3, 542.9)
RPMTorque=( 4000.0, -102.9, 578.1)
RPMTorque=( 4500.0, -113.9, 593.1)
RPMTorque=( 5000.0, -124.0, 598.1)
RPMTorque=( 5500.0, -132.8, 598.1)
RPMTorque=( 6000.0, -140.1, 589.8)
RPMTorque=( 6500.0, -145.6, 576.4)
RPMTorque=( 7000.0, -149.0, 554.6)
RPMTorque=( 7500.0, -150.0, 504.4)
RPMTorque=( 8000.0, -148.4, 417.4)
RPMTorque=( 8500.0, -143.9, 287.7)
RPMTorque=( 9000.0, -136.1, 127.7)
FuelConsumption=5.50e-5 // affected by throttle position and engine speed
FuelEstimate=0.70 // fudge factor for differences between vehicle types (used for lap estimates and AI pit scheduling)
EngineInertia=0.230
IdleThrottle=1.0
IdleRPMLogic=(1050.0, 1250.0)
LaunchEfficiency=0.969
LaunchRPMLogic=(4000.0, 5000.0)
RevLimitRange=(7500.0, 100.0, 0)
RevLimitSetting=0
RevLimitLogic=0.0 // RPM range around current setting where rev limiter operates
EngineMapRange=(0, 1, 5) // 0 = most driveable, max = most power (low gears only) (unimplemented)
EngineMapSetting=2
EngineBrakingMapRange=(0.0, 0.00025, 6) // input throttle is ranged from minimum to 100%, with the minimum = setting * step * RPM,
EngineBrakingMapSetting=2 // i.e. if you want 10% throttle at 6000 RPM, set the middle number to 10/6000 = 0.00167
OptimumOilTemp=95.0 // degrees Celsius at which engine operates optimally
CombustionHeat=40.0 // degrees Celsius added per liter of fuel burned
EngineSpeedHeat=12.000e-004 // heat added linearly with engine speed
OilMinimumCooling=7.50e-003 // heat dissipated without oil/water transfer
OilWaterHeatTransfer=(3.962e-001,7.925e-005) // heat transfer from oil to water (base, w/ engine speed)
WaterMinimumCooling=3.962e-003 // base heat dissipated without velocity
RadiatorCooling=(1.592e-004, 10.039e-005)// cooling rate with velocity (base, per setting)
LifetimeEngineRPM=(7495.0, 95.0) // (base engine speed for lifetime, range where lifetime is halved)
LifetimeOilTemp=(100.00,3.00) // (base oil temp for lifetime, range where lifetime is halved)
LifetimeAvg=14800 // average lifetime in seconds
LifetimeVar=3250 // lifetime random variance
EngineEmission=(0.20, 0.60, -0.4) // where flames and smoke are emitted (relative to ref frame at rear axle)
EngineSound=(0.20, 0.60, -2.5) // where engine sound is emitted (relative to ref frame at rear axle)
SpeedLimiter=1 // whether there is a pitlane speed limiter
OnboardStarter=1 // whether vehicle restarts when stalled
StarterTiming=(1.5, 0.0, 0.0) // average and variable cranking time, then blend with starting sound


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Proton_gears.ini

[GEAR_RATIOS]
ratio=(10, 36) // 3.600
ratio=(10, 35) // 3.500
ratio=(11, 38) // 3.455
ratio=(20, 67) // 3.350
ratio=(10, 33) // 3.300
ratio=(05, 16) // 3.200
ratio=(11, 34) // 3.091
ratio=(10, 29) // 2.900
ratio=(12, 34) // 2.833
ratio=(10, 27) // 2.700
ratio=(12, 32) // 2.667
ratio=(10, 25) // 2.500
ratio=(14, 34) // 2.429
ratio=(10, 23) // 2.300
ratio=(15, 34) // 2.267
ratio=(20, 43) // 2.150
ratio=(14, 29) // 2.071
ratio=(10, 20) // 2.000
ratio=(18, 35) // 1.944
ratio=(10, 19) // 1.900
ratio=(14, 26) // 1.857
ratio=(10, 18) // 1.800
ratio=(50, 89) // 1.780
ratio=(14, 24) // 1.714
ratio=(20, 33) // 1.650
ratio=(08, 13) // 1.625
ratio=(15, 24) // 1.600
ratio=(40, 63) // 1.575
ratio=(20, 31) // 1.550
ratio=(40, 61) // 1.525
ratio=(14, 21) // 1.500
ratio=(40, 59) // 1.475
ratio=(20, 29) // 1.450
ratio=(19, 27) // 1.421
ratio=(10, 14) // 1.400
ratio=(50, 69) // 1.380
ratio=(19, 26) // 1.368
ratio=(25, 33) // 1.320
ratio=(10, 13) // 1.300
ratio=(18, 23) // 1.278
ratio=(16, 20) // 1.250
ratio=(40, 49) // 1.225
ratio=(20, 24) // 1.200
ratio=(17, 20) // 1.176
ratio=(16, 18) // 1.125
ratio=(10, 11) // 1.100
ratio=(18, 19) // 1.056
ratio=(10, 10) // 1.000
ratio=(31, 30) // 0.968
ratio=(20, 19) // 0.950
ratio=(40, 37) // 0.925
ratio=(21, 19) // 0.905
ratio=(16, 14) // 0.875
ratio=(20, 17) // 0.850
ratio=(40, 33) // 0.825
ratio=(22, 18) // 0.818
ratio=(20, 16) // 0.800
ratio=(40, 31) // 0.775
ratio=(16, 12) // 0.750
ratio=(23, 17) // 0.739
ratio=(40, 29) // 0.725
ratio=(20, 14) // 0.700
ratio=(25, 17) // 0.680
ratio=(24, 16) // 0.667
ratio=(20, 13) // 0.650

[FINAL_DRIVE]
bevel=(1, 1)
ratio=(10, 45) // 4.500
ratio=(10, 40) // 4.000
ratio=(10, 35) // 3.500
ratio=(10, 30) // 3.000