These cross sectional cuts were made to see what the porting possibilities were for these heads.   I hope these photos show clearly the similarities and differences.   Your feedback is welcome but if you disagree tell me why.   I intend to update this with your comments even if they disagree with mine and may delete my comment and use yours, if yours seems more useful.

These heads, C4AE-G and C8AE-H, are not "virgin"; they've been used and abused.   I will refer to them as the G or early head and the H or late head.   The late head has the valves slightly sunk into the ports due, probably caused by running unleaden gasoline.   See the page on Port Position for a description of the differences in the port design.

Please note that the cuts are not perfectly square either vertically or left to right.   A power hack saw (or at least the ones used to make these cuts) is not able to make precision cuts.   Nor are the cuts exactly in exactly the same place although they are close.

The first picture, is of both heads with the section cuts marked with white chalk.   The C8AE-H is at the top.   There was only one cut that is important and it was right through the center of the bowls.

The photo of the C8 bowls which is cut right down the center of the valve guide, shows the bowls and their wall thickness.   The photo of the C4 bowls is similar.  

E-mail me at bsprowl@belsouth.net if you want me to send you a compressed high quality file of these pictures.   (It may take me a few days to response to your request.)