I want to add more than 20 drivers in LFS singleplayer, like in the events, where there are 40 something drivers. How do I do that?

You're a demo user, so you cannot have more than 12 drivers in single player (either you + 11 AI drivers or 12 AI drivers). In S1, S2 and S3 licensed events, it is possible to have up to 32 drivers in single player and 40 drivers in multiplayer.

Quote from tankslacno :

You're a demo user, so you cannot have more than 12 drivers in single player...

Hmm... well, I read in the manual that you can have no more than 20....

Quote from Lewis Hamilton II :

Hmm... well, I read in the manual that you can have no more than 20....

Can you please tell, where exactly on the LFS Manual you found that info? (so we can fix it, if it's wrong)

Quote from MandulAA :

Can you please tell, where exactly on the LFS Manual you found that info? (so we...

It's in Game Modes->Single Player when going from the main page

Quote from Pukyy :

It's in Game Modes->Single Player when going from the main page

Thanks! What I fixed is the number of maximum AI cars in a single player race for S1+ modes, which is 32 currently (it was 20 and even 24 in the article, confusingly). For demo mode, as tankslacno described and also the article had it correctly, there can be a maximum of 12 AI cars (or 11 + you), so in this case there was nothing to fix in the manual.

Quote from MandulAA :

Thanks! What I fixed is the number of maximum AI cars in a single player race...

No problem, glad to help