DOES ANYONE HAVE FLOW BENCH NUMBERS FOR PORTING AROUND THE INTAKE AND EXHAUST VALVES ON A 906 HEAD OR THE LIKE, TO ELEVIATE SHROUDING? I AM REFERRING TO THOSE WITH 2.14, 2.18, 2.20 INTAKES AND 1.81 OR 1.88 EXHAUST VALVES.

I AM THINKING THE NUMBERS COME IN AROUND 5 CFM OR SO?