[SFfiredog]

according to Shelby literature, the stage II port job flows 320 intake and 235 exhaust. Who knows at what valve lift. The combustion chamber on the Shelby heads is confirmed at 82 cc out of the box.
The E-brocks are not avaliable complete with the big valves (2.19/1.75) like the Shelbys and the valve job makes a big difference in flow #s. For example, Neil at Gessford Machine can get you 345 intake and 245 to 250 exhaust with a hand port job.
Keith Kraft Racing and Kuntz & Co can get you 365 intake and 265 exhaust with a not too radical CNC port job. If you have the small valve E-brocks on your motor now you should notice a good pick up in power, but not a huge bunch because you are losing some compression.
--Mike