Do you think it would be usefull to have place were those ressources would be gathered?
Yes, in terms of specifications. However sources need to be quoted rather than unattributed numbers just being thrown up into a thread. Appointing a curator or two to make sure posts conform would make it more beneficial to all.
When it comes to pictures, though, I think Fat-Alfie's approach works better.
For what it's worth, you'll find my database of links to free lidar for specific tracks is available at https://drive.google.com/open?id=1TC3ZEGzZtE7Ywmzf2UOlrZRaMbj_BOoIKkJHDtIPSpM. Haven't yet posted some overdue updates...
I'm also compiling a database of aerodynamic data (absolute lift & drag numbers) that's nearing 150 cars, but it's not ready for public consumption.