any ideas on what it is?

 

You want us to guess? POST a picture.

And what car and engine? Give details. Any symptoms?

 

Looks like it could be a relief valve from your oil pump. Is that pan still off? There should be a threaded hole for a plug of some sort. the plug holds spring and this valve inside of the oil pump. Could be the reason why your oil pump is not getting oil to the filter as you mentioned in your other post.

Other possibilities are the block orifice oil control valve. But I'm just guessing.

 

It is still off I'll have to check tomorrow but wouldn't there have been other stuff in the pan if that were the case.

 

looks like its the part for the oil pump with the spring in it. doesn't look like an orifice since it has a hollow part for the spring

 

Heh kinda looks like an LMA

 

i agree with thos who think its the pressure relief valve. If that is in the bottom of the oil pan where is the rest of it, the spring? If that is the pressure relief valve you are running without any pressure.

New oil pump time!

 

Do you recall taking apart the oil pump at all? I hope you guys are planning to check the health of that head and the cam journals.

 

I did try to open the cover on the oil pump to port it but was only able to get 2 of the Philipes screws out an the rest of them striped so I put the 2 back in and didn't mess with it after that.