Not possible. you can only mix the sound of the classic cars nothing else.
So taking for example the Rfactor sound files and making them compatible for F1 2013 is not possible? Would be such a shame. F1 2013 did a dissapointing job on that car then ... I think lot's of people expected a realistic V12 engine sound on that car...
But changing it to V10 like the 1996 Ferrari is possible? Could it be done in a mod or is it something you can do with changing files ?