If you are using only the RSCT23 with different liveries, you can also use TeamEditor 3.5 by Lo2k: the tyres setting are the same for all the cars when applied.
If you are using different carshapes into your cars.wad, reinstall
gp4tweaker_v1045_ReloadedRead the instructions carefully:
1- Put the gp4tweak.dll file into your C:\WINDOWS\SYSTEM32 folder
2- Into your main Grand Prix 4 folder, put the gp4tweak_data folder and the gp4tweak.ini file (from the extra/ config template folder of the archive)
3- Put the gp4_exe_patch.exe file into your main Grand Prix 4 folder (from the extra folder of the archive) and click on this file to apply the patch.
Then, edit your tyrepos.ini file and your gp4tweak.ini file to enable tyre position tweak.
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