I am looking for some cores so I can get them ported. Are all the aluminum LT1 heads the same.
Are there certain ones to avoid?

 

IIRC, the earlier ones are the best for porting, I seem to rememver them having the most material

 

Yeah apparently if you are going for an all out race port then its best to use the pre-96 heads because they have more meat to port out.

If you just want the typical port with larger valves then any heads should do I imagine.