#96 heads & engine question
 

Building a 1970 lemans/gto convertible, and new to the fourm. I have a 1968 400 engine, and #96 heads i think from 1971. What is up with the open chambered exhaust ports on the head? Do they serve any performance purpose? The 1968 block has a timing chain cover that is different than a 1970. Does the 1970 timing chain cover fit on a 1968 400 block? Thanks, any info will help.

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