Narrow-gutted

In this case Rolf Eliasson has opted for length, although an 8'5" beam isn't excessively narrow-gutted on a 25'7” LWL.

Source: wiktionary

She was a narrow-gutted, finely shaped thing (a narrow beam for her length, and typical of the period). She was once a beautiful vessel and would have enhanced any waterfront of the period – 'Even now' the skipper had mused, looking at her with just a little affection.

Source: wiktionary

It looked like a typical gyppo logging camp boat, a sad-looking thirty-two-foot hulk on its last stop before the boneyard. It was a long, narrow-gutted, low-slung thing.

Source: wiktionary

A round-barrelled, trussy horse of a hardy constitution will bear a dose of medicine which would be destruction to a slight and narrow-gutted one, and you should therefore be extremely cautious how you administer such quantities as you may occasionally see prescribed as physic in veterinary works, without previously ascertaining, as far as you can, the capabilities of your horse for sustaining their operation.

Source: wiktionary