Hello! I was under my car checking stuff out and I saw this weird block of metal under my car that is bolted to what appears to be near the sway bar or an engine mount. In the video you can clearly see its loose and wobbles. I wasn't really able to tighten it because the block turns with the bolt and I dont know if it's supposed to be like that. Any ideas on what this might be would be much help! (Btw I have a 2004 350z)
Video:

 

probably a damper for NVH

 

This video is terrible. But I've never seen that on any G or Z, and I know every OEM component of the Z33's/V35's

 

Yeah I agree videos horrible xD. Ive been looking up pictures of 350z and that spot is just empty on theirs so I have no idea

 

definitely get some pictures with flash

 

That could have been a mount for the machine Nissan used when mating the powertrain to the chassis at the factory. I've found a few bits and baubles that had no explanation on my car as well and took them off without any repercussions. Maybe your car was built on a Friday and Akira simply forgot to take to lift mount off.

 

Okay cool, just wanted to know if it was something to worry about. As long as it wasn't a loose mount or key component of the car then I will probably just remove it. I will post some better pictures before I do.

 

What you have found is a solid block of "mass" to control the vehicle's natural tendency for vibration that is in tune with the vehicle's natural frequency. Removing said block won't necessarily hurt anything but may contribute to odd vibrations and noise at particular speeds. This is NOT unique to Nissans as it is a practice used by most, if not all, mfgrs to cut NVH (as was mentioned early in this thread.)

It's usually found on roadsters (no roof) but will vary by year. If you look at your car very carefully, odds are you will find another, similar block somewhere diagonal to where you found the existing one. (Sometimes inside the cabin.)

Removing it will do nothing for your vehicle, one way or the other.

 

Interesting! I am guessing it being wiggly like that is normal?

 

As stated... NVH damper. Yes, it's supposed to wobble. If your Z is just a daily driver, leave it alone. If you're building a track car, take it off.