Board Thread:Game Updates/@comment-3502824-20170107021331/@comment-26574811-20170110083849

【機関部強化】系装備シナジー効果の実装 「機関部強化」系装備【改良型艦本式タービン】と【強化型艦本式缶】を同時に 装備することで、艦の機関部を抜本的に強化し、艦速を向上させることが可能になります. 艦速【低速】の艦娘を、【高速】化することも可能となります.

Aside from opening the expansion slot for engine-related equipments, if you put BOTH Improved Kanhon Turbine AND Enhanced Kanhon Boiler on a slow ship girl, she well become "fast". Both equipments are availbale through new quests.