It could be magnesium.

 

Why don't you just order part # 3yf-11187-00-00

If I'm understanding you correctly, you just need the oval shaped cover that goes over the intake valve side, is this correct?

 

well guys, it's cast aluminum, thank god there is a machine shop at work. They welded it for my CROOKED though, so I get to set up on the mill and fix it up, should work.
Bash> it's the whole rocker cover I cracked, which to buy is $430 my price and COMES WITH THE HEAD ONLY! there are matching serial #'s on the rocker cover and head which must be for when they assemble the raptors so that they use mated cases.

it's lunch time now, back to work and to grind off the excess weld and crooked part!

 

well after some more welding, milling, grinding and sanding and drilling good as new (I HOPE!)