454 heads

I am ordering headers and need to know what heads I have,round port or "D" port.How do i tell?
Fred

 

Take an exhaust manifold off and look.

 

I think all of the cast ones are round/ kinda square. I had a set of aluminums GM heads and they were "D" ports. Got a pic?

 

picture on the way.

 

Here is the photo

 

Round.

 

D ports http://images.google.com/imgres?img...ev=/images?q=d+port+big+block&um=1&hl=en&sa=N

 

Thanks