rect port
Back in the early 70's, when there were alot of 396 oval port engines with cast iron intakes from the factory, we all pulled them off and put factory 375 horse rectangular port aluminum intakes on the 325 and 350 horsepower engines.
I swear we thought they were faster even with the port mismatch. Maybe it was just losing the weight of the iron intake?
I can also remember using the wrong intake gaskets the first time and having a hell of a big vacuum leak. Took a couple beers to figure that one out.