The following part can be inserted into a mod's vehicle xml ("motorized" section) to modify the behavior of the smoke.
The attributes "isEnabled", "intensityFactor" and individual factors can be left out when you don't want to override them.

<exhaustExtension excludeVehicle="false" intensityFactor="1.0"> -- By setting "excludeVehicle" to true, the current vehicle will be excluded from the ExhaustExtension script. With "intensityFactor", you can modify the general intensity of the smoke for this vehicle.
    <motorStart factor="1.0" /> 				-- intensity factors of the individual trigger events
    <cutTree factor="1.0" />
    <delimbTree factor="1.0" />
    <engineLoad factor="1.0" threshold="0.5" /> 		-- threshold (0.0 - 1.0, default: 0.5) is the load value where the particle effect starts
    <damagedVehicle factor="1.0" threshold="0.85" /> 		-- threshold (0.0 - 1.0, default: 0.85) is the damage value where the particle effect starts
</exhaustExtension>
