https://fr.wikipedia.org/wiki/France_(paquebot)

"Vitesse en service : 31 nœuds sur quatre hélices"

"Caractéristiques techniques
Longueur 315,7 m (hors-tout)
299,2 m (flottaison)
290 m (entre perp.)
Maître-bau 33,7 m
Tirant d'eau 10,5 m
Tirant d'air 66,9 m
Déplacement 57 607 t
Port en lourd 13 960 tpl
Tonnage 66 348 tjb
Propulsion 4 hélices fixes, ∅5,8 m
4 groupes CEM-Parsons
Puissance 160 000 ch
Vitesse 31 nœuds"


https://en.wikipedia.org/wiki/SS_France_(1961)

"Below the waterline, the forward engine room was dismantled and the two outboard propellers were removed to reduce fuel consumption as a high service speed was no longer required as she was now a cruise ship."

"Her engines consisted of eight high-pressure, super-heating boilers delivering 64 bars (930 psi) of pressure and 500 °C (932 °F), all weighing 8,000 tons. This delivered 175,000 horsepower (130,000 kW) and provided for a service speed of 30 knots (56 km/h; 35 mph) and a maximum speed of 35 knots (65 km/h; 40 mph), with a fuel consumption of 750 tonnes of oil in a 24-hour period. The machinery turning the four propellers was divided into two fore and aft groups, as was the electrical generating station.[4]"

"General characteristics
Tonnage:
66,343 GT (1961)
70,202 GT (1984)
76,049 GT (1990)
Length: 316.1 m (1,035 ft)
Beam: 33.8 m (110.6 ft) waterline
Draft: 10.8 m (34 ft)
Decks: 12
Ice class: none
Propulsion:
Geared CEM-Parsons turbines
quadruple propeller (1961–1979)
/ twin propeller (1979–2008)
Sail plan: none
Speed: 30 knots (56 km/h; 35 mph) approx.
Capacity:
1961–1974
First class: 407
Tourist class: 1,637
1980–1990 - 1,944 passengers
1994–2003 - 2,565 passengers
Crew:
1961–1974 - 1,253
1980–1990 - 875
1994–2003 - 875
Notes: Cost US$80 million approx."

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Note added at 2 hrs (2017-03-18 20:00:14 GMT)
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Definition of "service speed": https://www.degruyter.com/view/j/pomr.2007.14.issue-1/v10012...

"Calculation of the mean long-term service speed of transport ship: Part II Service speed of ship sailing on regular shipping route in real weather conditions

Tadeusz Szelangiewicz
/ Katarzyna Żelazny
Published Online: 2007-06-20 | DOI: https://doi.org/10.2478/v10012-007-0005-1
Calculation of the mean long-term service speed of transport ship: Part II Service speed of ship sailing on regular shipping route in real weather conditions

Service speed obtainable by a ship in real weather conditions when sailing on a given shipping route, is one of the major parameters which have great impact on ship operation costs. The so far used, very approximate method of service speed prediction based on "service margin", is very little exact. In this paper a new method based on additional ship resistance dependent on mean statistical parameters of wave and wind occurring on a given shipping route, is presented. The mean long-term service speed is calculated on the basis of the calculated additional resistance and the screw propeller and propulsion engine parameters. Also, a new definition of service margin and a way of its calculation is presented apart from the results of the mean service speed calculation depending on ship's type and size and shipping route."