For example to change McLaren performance:
Go to asset_groups\f1_2016_vehicle_package\teams\mclaren\wep
Open mclaren.erp with Ego Erp Archiver
Under XML files there should be a mclaren.vtf
Go to XML files -> export and save it
You can edit the file with Notepad++
Some examples of things you can change:
* FuelECU - FuelBurnScale, FuelPowerScale ... ie. FuelPowerScale can be used similarly to engine_power_scale used in the previous games' ctf files. I haven't tried FuelBurnScale at 0.0, but 0.1 even works with FuelPowerScale greater than 1.25. Fun stuff if you want ridiculous wheelspin (FPS=2.0) or more severe variation through the fuel mixes, etc.
* BrakeECU - BrakeFront, BrakeRear
* Chassis - Mass
* Tyre (Front, Rear) - MinGrip, MaxGrip, GripMultiplier
* Engine, FuelTank, FuelECU, BrakeECU, Chassis, Steering, CoreAero, Differential, Brake, Tyre, Suspension, Wheel, etc
You can also copy and paste whats in the mercedes file to the other cars to make them quicker.