Afr 165 head ?s

[ranger50toy]

I have an older set of 165cc heads that have a groove in the combustion face. I have changed to Cometic head gaskets this weekend due to coolant leaks and found that they have a specific gasket for these heads. Did this groove get deleted? What does it do?

 

[Paul]

Call AFR.

 

[95-stang]

I have some AFR 165 heads, bought them a few weeks back and they advise Fel Pro [for 1983 - 1995] Fel-Pro #1011-2.
Looks like the design might have changed?

http://www.airflowresearch.com/sbf_install.php