Rattling noise
 

11 R3
Just had stainless steel brake and clutch lines
Installed
Motul RBF 600 added
Brakes bled
Now with a rattling sound on acceleration from
Under the center of hood; with a/c on or off and
Worse from 2-5K rpm
Power is normal
All other aspects of drive are normal
If you have any thoughts, please advise
Thanks

Check motor mounts for unusual wear / cracking? Long shot on a 2011. Video might help.

Also check engine under pan and fender liners

Pinging is often described as a 'rattling' sound and it is related to rpm. If you think that is a possibility then check your fuel (use good premium) and pull codes to see if you have anything pending.

the clutch line goes right down the middle of the engine bay right in front of the firewall. The line is probably rubbing up against the firewall. Follow that line from the top down.