Strokers like a lot of air at higher RPM, on a 392" motor I wouldn't personally run a port any smaller than 205-215CC, even if it only flowed the same air on the bench as a 185 (granted more efficient port per CC of Area) a long stroke motor will like the bigger port at high RPM better, ESPECIALLY in a light car like a Cobra that doesn't want or need a lot of low end velocity to get it moving. Remember a flowbench only measures air, at a 12.5:1 A/F ratio 7 percent of what flows through the port is atomized (but still solid) fuel, if the velocity gets too high the fuel falls out of suspension and will ride the walls and then the walls become even more of a restriction to flow and the BSFC goes down.
A comparison of 170 vs 205CC intake port Trick Flow heads on a 347" SBF made 50 more HP, granted the 205's are cnc ported and flow more but the 205 ports are obviosly not too big for even 347 cubes in terms of torque/hp.
http://trickflow.com/product/fordcyl...cnctwisted.asp