[hi-tech cobra]

Flow number are my best guess after talking with several people who port gt-40x heads regularly.

Intake: 270 cfm at .550" lift
Exhaust: 170 cfm at .500" lift

The heads were hand ported by a well known nascar guy in Charlotte. I asked the machine shop today and he can't recommend anyone in Jacksonville, FL to flow test the heads. He said it wasn't necessary. I would like to have them flow tested, just don't know where to get it done.

Kevin you asked how much the ports were opened up. How do I check, mic the intake & exhaust openings? Do you think the valve size is a problem?