can someone please tell me what this triangular space is for. ive seen pictures with something attached here and some pictures its empty like mine(picture 1). also, is this normal to see in our engines? (picture 2)

picture 1

picture 2

 

First picture is the the mounting point for the secondary air injection valve, sometimes erroneously called EGR.
2006 or newer cars do not use this but the casting is still there.
Not sure what to look for on the second picture, casting marks?

 

In the second pic I believe you're referring to the casting marks as flanders mentioned above. If so that's completely normal. Nothing is making contact with that area or riding on it, so it makes sense to leave it rough like that as it serves neither fit nor function to be made to look nice.

 

I was indeed referring to the casting marks. At the time I did not know what that was though so I was a bit nervous.Thanks for clearing that up for me guys.