What of the two Aluminum heads are the better ones? I cant remember.
TIA

 

The early ones flow less as cast but offer more meat for porting, the later flow more as cast but are thinner with less room to port. Answer depends on what is your definition of better?
I would not go through the trouble of swapping out old casting for new for the small as cast flow difference either. I do not have the casting numbers handy either but hopefully this has you pointed to what you wanted to know.

 

Thanks, I need to find out which ones had more room for porting.

 

The 561 cast heads are the heads that came on 96-97 camaros. I forget the casting numbers of the 93-95 cars. The difference was about 10% more air flow or so with the 561. There was a comparison I found on here one time, maybe you can search for it.

 

The early casting was used from 92 to sometime mid 95.

 

So the earlier ones have the most meat on them for porting? (92-95)

 

Yes

 

Where is the casting # located? Do i have to pull a valve cover to check to see what i have?