Daimler V8 engines

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Daimler V8
Daimler SP250 V8 Engine 1963 3737131536.jpg
1963 Daimler SP250 V8 Engine
Manufacturer The Daimler Company Limited
Combustion chamber
Configuration 90 degree V eight-cylinder[1]
  • 4½ litre: 4.561 litres (278 cu in)[2]
  • 2½ litre: 2.548 litres (155 cu in)[1]
Cylinder bore
  • 4½ litre: 95.25 mm (3.8 in)[2]
  • 2½ litre: 76.2 mm (3.0 in)[1]
Piston stroke
  • 4½ litre: 80.01 mm (3.2 in)[2]
    2½ litre: 69.85 mm (2.8 in)[1]
Cylinder block alloy Cast iron[3]
Cylinder head alloy Aluminium alloy[3]
Valvetrain OHV by pushrods and rockers[2] from a single camshaft,[4] two valves per cylinder, hemispherical head[5]
Compression ratio
  • 4½ litre: 8.0:1[2]
  • 2½ litre: 8.2:1[1]
Fuel system
  • 4½ litre: Carburettors—twin S.U. HD8; fuel pump—SU electric
  • Aua 61[2]
  • 2½ litre: Carburettors—twin S.U. HD6[1]
Fuel type Petrol[2]
Oil system Filter—Full flow replaceable element[2]
Cooling system Water[2]
Power output
  • 4½ litre: 220 bhp (160 kW; 220 PS) @ 5,500 rpm[2]
  • >2½ litre: 140 bhp (100 kW; 140 PS) @ 5,800 rpm[1]
Torque output
  • 4½ litre: 383.7 N·m (283.0 lbf·ft) @ 3,200 rpm[2]
  • 2½ litre: 155 N·m (114 lbf·ft) @ 3,600 rpm[1]
  • 4½ litre: 31.25 in (793.8 mm)
  • 2½ litre: 30 in (762.0 mm)
  • 4½ litre: 25.5 in (647.7 mm)
  • 2½ litre: 24 in (609.6 mm)
  • 4½ litre: 31 in (787.4 mm)
  • 2½ litre: 27 in (685.8 mm)
Dry weight
  • 4½ litre: 498 lb (226 kg)
  • 2½ litre: 419 lb (190 kg) exc. flywheel

Daimler V-8 engines were designed for the Daimler Company by Edward Turner and produced from 1959 to 1969. Initially used in the SP250 sports car and the Majestic Major saloon, the engine was mostly used in the Daimler 2.5 V8 (later named V8-250) saloon made with Jaguar Mark 2 unit bodies from 1962 to 1969. Approximately 20,000 of the 2.5-litre version of the engine were made for use in the SP250 and the 250 saloon, while approximately 2,000 of the 4.5-litre version were made for use in the Majestic Major saloon and its limousine variant which remained in production until 1968.

Design and development[edit]

Shortly after being appointed Managing Director (Chief Executive) of BSA's Automotive Division in 1956, Edward Turner was asked to design a saloon car powered by a V8 engine.[6][7] Turner and his design engineer Jack Wickes began considering the initial concept of their new engine by examining the manual and spare parts list of a Cadillac V8 engine.[note 1][6][8] Using a pushrod overhead valve system kept down design, development and production costs and allowed Turner to base the design of the cylinder head on those he developed for Triumph motorcycles[6][9] including the use of hemispherical combustion chambers.[10] Adapting the Triumph head design for use in a saloon car engine required much work in reducing friction and improving timing.[11] Much of the development of the prototype engine was carried out by Dr. J. N. H. Tait.[12] Tait had been involved with Donald Healey in the early post war years, working successfully on modified Riley 2½-litre Big Four engines, the final incarnation of which was used in 1953 Zethrin Rennsport prototype, delivering close to 200 bhp with surprising tractability.[citation needed]

The two sizes of the Daimler derivative engines share similar external dimensions and design, including bore spacings, and one can be bolted in place of the other.[citation needed]

Limited investment in tooling for the 2.5-litre engine led to limited production capacity, with a maximum weekly output of 140 engines. This prescribed maximum output was never achieved during the production of the engine.[13]


The 90 degree V8 engine has part-hemispherical combustion chambers with two overhead valves per cylinder operated by push-rods from a single chain-driven camshaft positioned centrally high up in the vee.[14] Aluminium alloy pistons with steel connecting rods run in a cast chrome-iron block with sand-cast high-tensile light alloy heads and crankcase housing a short stiff dynamically balanced crankshaft carried on five bearings.[note 2][3] The nose of the crankshaft carries a torsional vibration damper, a four-bladed fan, and the pulley for the triangulated thin belt drive for the dynamo and water pump.[3] The dynamo is located between the cylinder blocks.[15] At the rear the drive is taken from the back of the camshaft for the distributor positioned high above the unit[16] behind the two semi-downdraught SU carburettors.[17] There is a separate exhaust system for each bank of cylinders.[18] Light alloy is used for the valve covers, tappet blocks, sump and inlet manifolds.[17] Cooling is by pump and fan with a thermostatic by-pass control.[19]


The engine first publicly appeared in the Daimler Dart but, after Chrysler objected to use of that name, it was called the Daimler SP250, a fibreglass bodied sports car aimed at the American market.

In December 1961 Daimler announced a marine version of their 2.5-litre V8.[20][21]

The 2.5-litre engine, only 30 inches (760 mm) in length and developing 140 bhp (100 kW) @ 5,800 rpm, gave better performance than Jaguar's own 2.4-litre DOHC in-line six, and after the 1960 merger the opportunity was taken to create an up-market Daimler V8 version of the Jaguar Mark 2. Between the years 1962 and 1969 17,620 Daimler/Jaguar V8s were built. Initially called the Daimler 2.5 V8, it was later called the Daimler V8-250.

Daimlers with 2½ litre engines
SP250 sports car 
V8-250 saloon 
2½ litre Daimlers

The 4.5-litre engine was used in the Daimler Majestic Major DQ450, which is now rare, but was a respected high performance saloon in its day. The engine was also used in the Majestic Major's limousine derivative, the DR450. The 4.5-litre was tested in a Jaguar Mark X and lapped the Motor Industry Research Association's high-speed test track at 135 mph (217 km/h) but was reportedly not put into production precisely because its performance was better than the original Mark X's.[22] All 4.5-litre V8 models sold were automatic, which makes connection to a manual transmission difficult.

Daimlers with 4½ litre engines
Majestic Major saloon 
DR450 limousine 
4½ litre Daimlers

Felday-Daimler hillclimbing special[edit]

Peter Westbury, an engineer from Surrey, England, competed in hillclimbing events in cars powered by Daimler V8 engines. Between the end of the 1962 RAC Hillclimb Championship season, in which he finished seventh in a V8-powered Cooper, and the beginning of the 1963 season, Westbury built a new hillclimbing special called the Felday-Daimler powered by a 2.5-litre Daimler V8 with a 2 in (51 mm) SU carburettor and a Roots supercharger. Westbury won the 1963 RAC Hillclimb Championship in the Felday-Daimler, setting course records at Craigantlet in Ulster and Dyrham Park in Gloucestershire.[13][23]

Glacier Grenade drag racing special[edit]

In 1970, Russ Carpenter and Tony Anderson built the "Glacier Grenade," a rear-engined drag racing special.[24] It was the first "All British" rear engined dragster of its type.[citation needed] Powered by a 2.5litre Daimler V8 it would compete in drag racing from March 1972 until 1989 when the car was outlawed from European racing. Russ began to drive the car in 1974 taking over sole driving duties after Tony's retirement from the sport in 1976 due to a spinal injury. Russ continued the car's development all the way through its racing life.[25] In 1980 it became the first drag car under 5.5 litres, and the first all-British car to complete a quarter-mile race in less than eight seconds.[24] By the time of its retirement, the car, using mainly stock engine parts,[citation needed] produced 1400 bhp and ran the standing quarter mile in 7.2 seconds at 180 mph.[26] The car was restored and was to be displayed at Dunsfold Aerodrome in Guilford in April 2014.[24]

In 2014 Russ Carpenter was inducted into the British Drag Racing Hall of Fame for his development of this engine and influencing others to use a British engine in a largely American engine focused Motorsport.[25]

End of production[edit]

Jaguar became part of the British Leyland Motor Corporation (BLMC) in 1968. BLMC chairman Sir Donald Stokes decided that the production costs of the Daimler V8 engine were too high and ordered its discontinuation.[27] The Majestic Major was discontinued without replacement in 1968, followed by the V8-250 in 1969.[28] By 1970 the Daimler range was reduced to the Jaguar XJ6-based Daimler Sovereign saloon and the Jaguar Mark X-based Daimler DS420 limousine, both powered by Jaguar XK6 engines.


  1. ^ Feedback. The Type 51 was the first Cadillac V8. Introduced in 1914, it was the standard engine for 1915 Cadillac models. It was a 90° design with an L-head (sidevalve) configuration and was water-cooled. This engine was designed under the leadership of Cadillac's chief engineer 1914-1917, Scottish-born D (D'Orsay) McCall White (1880 -), later a vice president of Cadillac.(Cadillac puts White in Vice-Presidency, Automobile Topics October 13, 1917 Volume 47) Hired by Henry Leland for his V-engine expertise from his employment as chief engineer at Napier, and previously Daimler at Coventry.
  2. ^ "The power unit has a cast-iron block, light alloy head and crankcase, with a short stiff dynamically balanced crankshaft carried on five bearings."—Smith 1972, p. 271. However, the source does not mention a chrome-iron block, aluminium alloy pistons, steel connecting rods, or the light alloy components being sand-cast or high-tensile
  1. ^ a b c d e f g h Smith 1972, p. 279.
  2. ^ a b c d e f g h i j k Autocar Road Test 1907, Autocar, 4 January 1963, Iliffe, Sons & Sturmey, London 1963
  3. ^ a b c d Smith 1972, p. 271.
  4. ^ Smith 1972, p. 276.
  5. ^ Smith 1972, p. 277.
  6. ^ a b c Clew 2007, p. 82.
  7. ^ Long 2008, p. 19.
  8. ^ Long 2008, pp. 19–20.
  9. ^ Long 2008, pp. 20–22.
  10. ^ Long 2008, p. 87.
  11. ^ Long 2008, p. 22.
  12. ^ Long 2008, pp. 22–23.
  13. ^ a b Douglas-Scott-Montagu & Burgess-Wise 1995, p. 279.
  14. ^ Smith 1972, pp. 276–277, 279.
  15. ^ Smith 1972, pp. 271–272.
  16. ^ Smith 1972, p. 272.
  17. ^ a b Smith 1972, p. 296.
  18. ^ Smith, Brian E. (1980). The Daimler Tradition (second revised ed.). Transport Bookman Publications. ISBN 085184 014 0. 
  19. ^ Smith 1972, p. 297.
  20. ^ Douglas-Scott-Montagu & Burgess-Wise 1995, pp. 279–280.
  21. ^ Smith 1972, p. 293.
  22. ^ Buckley 2003, p. 176.
  23. ^ Smith 1972, p. 282.
  24. ^ a b c Langlois 2014.
  25. ^ a b "Russ Carpenter - British Drag Racing Hall of Fame". www.britishdragracinghof.co.uk. Retrieved 2016-07-04. 
  26. ^ Long 2008, p. 159.
  27. ^ Boddy 1971, p. 13.
  28. ^ Long 2008, p. 137.


External links[edit]