On the 440 Sp2P we sat it down next to a 1968 383 2bb Iron boat anchor. the ports were about the same on both the carb and head ends. So yes a Marble may block it but its a big marble.
Understanding on a 440 a 383 2bbl port is NOT a race port but its not that bad if you KNOW you will not be drag racing your 32 foot long Winnabago. Will it pull past 4500 RPM, YES but it will be lazy.
Retired, US ARMY 1973-1994
ASE mechanic, Electrical 1994-1997
Retired GTE/VERIZON/FRONTIER 1997-2015
Posting cheap tech help (CRAP) here since Nov 97, 1000's of posts, some may be good.
03 Suzuki Burgman 650(Burger King) Scooter
65 Formula S Cuda
78 Little Red Express Truck
98 Buick Regal (wifes car)
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