Thanks Pat. I will be running 4" exhaust, outsiders quite similar to the '66 Ford Cobras for the occasional street use. The collector for racing will be a 4" "tuned" to length by the old match the plug reading to the reading on the white chalk inside the collector method. I believe the Edelbrock Victor heads are the Ford port arrangement, don't hold me to that, though. I know the John Kasse designed head is a BBC flange. Have you ever used the merge collectors on a big block??? I know on a Windsor they build quite a bit of extra low end into the motor????