been getting huge fps drops lately

beamng drive used to run perfectly fine but lately it started to have horrible fps drop second i hit the throtle. my graphical settings havent changed even a bit for last 5 months and when i revisit my older clips from beamng the game is buttery smooth. getting 70 fps and suddenly dropping to 13 never happen to me before and my rig isnt an issue because every other game works perfecty fine