How many non-treaty heavy cruisers Japan could build

How many fast 20,000-ton heavy cruisers could Japan build instead of the Yamato, Mogami, Tone, and Ibuki programs?

Only about fourteen or fifteen in the proposed set, because engine production would prevent Japan from converting all the saved heavy-ship effort into cruiser numbers.

The counterfactual proposes fast, non-treaty cruisers with three quadruple eight-inch turrets instead of several historical Japanese capital-ship and cruiser programs. The panel does not expect a dramatic numerical windfall. Removing Yamato-scale hulls frees slips and materials, but producing enough engines for many fast 20,000-ton ships remains difficult. The rough estimate rises from the eleven ships named in the premise to only about fourteen or fifteen. This is therefore an industrial-capacity problem rather than a simple exercise in dividing battleship tonnage into smaller hulls.