also on ebay were the
FORD TRANS AM TUNNEL PORT CYLINDER HEADS http://cgi.ebay.com/ebaymotors/FORD-302-TRANS-AM-TUNNEL-PORT-CYLINDER-HEADS-NOS_W0QQcmdZViewItemQQcategoryZ33617QQihZ015QQitemZ250047377225QQrdZ1
Chevy was working on the Porcupine head as a response to the Ford Tunnel port head. From what I read, they both made good power but at higher RPM so there was less low RPM torque for pulling off the corners and the higher engine RPMs hurt engine reliability.
The Ford Tunnel port heads were not very successful and had a lot of engine failure so the Porcupine heads were not really needed.
It's amazing the extent that Chevy and Ford went to just to win in Trans Am