For 1939 Daimler offers three six-cylinder models: the Fifteen 2½-Litre, Twenty and Twenty Four. Engine cubic capacities are 2522, 2565 and 3317 cc respectively. There are also two eight-cylinder models, namely the 4-Litre Straight Eight (3960 cc) and the Straight Eight (4624 cc).
ES24 or Twenty Four has six-cylinder OHV engine developing 75 bhp at 3600 rpm and is rated at 23.81 HP. Like all other Daimler models it features Fluid Flywheel with pre-selective epicyclic four-speed gearbox and worm-drive rear axle. Suspension is by semi-elliptic leaf springs, front and rear. Brakes are Girling mechanical with Clayton Dewandre vacuum servo assistance. Wheelbase 10 ft 4 in. Tyre size 6.50-17.
A 'Special Sports' version of the 15 hp called Dolphin was announced in April 1939 with 4-door cabriolet bodywork (all-weather tourer) by Charlesworth Bodies of Coventry and a high-compression (increased from 5.5:1 to 7:1) 90 b.h.p engine (a 36% increase on standard output) with twin carburettors, redesigned porting and light-alloy cylinder head. A higher final drive ratio was provided for 'exceptionally easy fast running'. Novelties for Daimler included a tachometer, and a fishtail exhaust with matching resonance.
Two Straight-Eights Landaulette bodied by Hooper delivered to King George on New Year's Day. One of them has Lanchester radiator.
Another Landaulette by Hooper was ordered by the King of Greece.
In responce to the international crisis Daimler builds a second Shadow Factory on a 62-acre site at Brown's Lane, Allesley, Coventry to build 200 Bristol Hercules aero-engines a month in wartime. They also developing a fast armoured scouting vehicle for the British War Office. First delivery took place in December.
2½-litre DHC built for King Geroge VI
S.C.H. 'Sammy' Davis and hid Dailmler Fifteen. He started from John o’ Groats and finished 22nd.