F1 2021 Tyre performances (and cars) improved - Unified Version ! (patch 1.18) 6.4

Hello,

1) copy the main part
2) copy the addon and overwrite

:)

Thanks ! I did less tests on 50% than 25% because it's very time consuming. I tested all race start at 50% and did several full races (included qualification phases), so i hope it's ok.

Thanks :)