Have read where the rF2 devs were at one time considering making available to modders the rF1 tire model to be used in rF2 ?, is this still the case ?, would make it far easier for folks doing the physics, grip etc. in rF2.
there is a tire store available online with plenty of examples of rF2 tires. rF1 is still owned by ISI and has zero connection now with rF2 which is owned by Studio 397. So no chance the rF1 tire would become available and most likely, it would not perform very well.
rF1 tire model is still present in rf2, it's used by AI and I think can be used by the player in dev mode so yeah they can make that available if they want to (they thought about doing that some time ago as OP stated but they didnt talk about it anymore). It'd perform better than the cpu hungry rf2 tire but ofc it's way less detailed
In Mod Dev, if you want to use ( to test ) TBC tyres ( although in RF2 they are no more exactly like they were in RF1 ), You can push Alt - T and You switch from TGM tyres to TBC. Same operation to come back from TBC to TGM. TBC are used only by AI drivers.