Stock intake vs performer?

69 Cuda 440 said

Intake Manifold Port Size Carburetor Height

Edelbrock Performer #2176 ....................... .97" x 1.95"............ 4.63"

Edelbrock #LD-4B ..................................... 1.05" x 1.95"

Edelbrock Performer RPM #7176 .............. 1.01" x 2.17" ........... 5.35"

1971 '340' Cast Iron #3512100 ................ 1.08" x 2.17" ........... 5.00"

Edelbrock Performer Air-Gap #7576 ......... .98" x 2.16" ............. 5.35"

Edelbrock Torker II #5076 ....................... 1.00" x 2.17" ........... 5.72"

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Thanks for the info Cuda 440.

I'm still unclear on how these specs are derived, how these numbers are measured?
Are the dimensions measured at the exit window? And Do they represent the dimensions through the full length of the runner?

I am being very specific because it does make a difference.

-AlV