Good question here, its not just a volume vs length one it also depends alot on hull shape of the bow and stern, deck heigth and width, flatbottom hull vs. displacement/rounder type and the type of water pushy/flat.
Looking at older&newer Dagger boats offhand, the Honcho and the CFS, the CFS@ 7'10''-75 gal. is a far more stable boat than the Honcho @7'9'' -66gal. due to hull shape more than the volume difference keeping in mind that the shape does take away some of the volume but it is the slicey tail that takes away the stability.
Now toss in the Super Ego@ 7'6''- 51 gal. losing length and volume in the nose from the Honcho you have a squirrel of a boat in waves and pushy water, the Kingpin Icon 63 @ 6'3'' -56 gal it is alot different from the Super Ego in the stability dept. with more volume but less length.
Then you have the RPM Max @ 9'2''- 75 gal. that alot of shops used to teach with longer than the CFS but same volume. Looking at the Mamba 8.0 @8'-57 gal. you have stabilty and handling with length and lower volume.
What it boils down the is hull shape more than anything else.
Hope this clairify's this topic some what.
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