The historical Town-class machinery produced about 75,000 to 82,500 shaft horsepower from four boilers. The comparison is the Brooklyn class, whose eight 600 psi boilers delivered greater power and much longer cruising range. Retaining four 850 psi units might raise Town-class output toward 132,000 shaft horsepower, while a three-boiler installation could preserve performance and release space. Either path changes cruiser employment through higher speed, longer economical range, or more room for armament and aircraft; the Arethusa and fast minelaying cruiser designs would feel the effect especially strongly. The Towns might approach 36 knots or use the efficiency gain to move toward American-style long cruising range.
Chapter · 50:26-57:09
Town-class cruisers gain speed or range
Town-class and smaller cruisers could use 850 psi plants for roughly 36-knot performance, longer range, or freed space for weapons and reconnaissance aircraft.