intake ports trivia

While cleaning up a couple of intake manifolds I noticed that the 4 bolt carb manifold had 1-1/4" dia. ports in it while the 3 bolt carb manifold had 1-1/8" dia. ports. I measured the ports on the matching surface of the '42 and the '47 cylinder blocks and they seem to be the same diameter as the 4 bolt manifold which seems logical. The question(s): what size are the intake ports on the '36 to '41 cylinder blocks? Did they increase the port size in the block to 1-1/4"dia in 1940 when they upped the displacement? and is there a "matching" 3 bolt carburetor manifold for those cars?

I can only answer for the '37s I have, but the block intake ports look to be 1 3/16", and the intake manifold ports are 1 1/8".

Thanks Cecil, that answers part of it. I suspect the increase in port size happened in '42 along with the 2-15/16" bore and they just kept it that way until the end of production.