conceptcarz.com

1934 Rolls-Royce 20 / 25 HP

World War I devastated Europe with upwards of eleven million Europeans losing their life and even more sustaining serious injury. Industry, transportation networks, homes, and factories were damaged or destroyed. Despite the devastation and loss, the workforce and infrastructure quickly recovered. Other countries capitalized on the absence of European competition, coupled with the prospects of new technologies and innovative ways of managing labor. During the 1920s, American economic growth increased by 42%, and by 1925, more than 25% of families owned a car thanks in part to mass production techniques. American manufactured goods and agriculture excelled due to less expensive production methods and superior build quality.

The peace treaties negotiated between 1919 and 1923 gave Europe economic stability, and the defeated Central Powers were forced to pay reparations to the European Allied Powers (albeit not America). Germany alone was forced to pay 132 billion gold reichsmarks.

Rolls-Royce manufactured aero-engines during World War I and would establish an enviable reputation for aircraft engines for both civilian and military purposes. Additionally, their Model 40/50 automobile would serve as a basis for the first British armoured car.

Rolls-Royce in the Post-War Era
Rolls-Royce emerged from World War I having gained expertise and experience in aero-engine production, and was fortified by its 40/50 hp 'Silver Ghost' automobile. Silver Ghost automobiles catered to the elite in society and had gained a reputation for being the 'Best car in the world' shortly after its introduced in 1906. Production would continue through 1926, with 7,874 examples built in total.

While Rolls-Royce stood on fine financial footing, the European market was devastated, and the pool of buyers able to afford a Silver Ghost had dwindled. Rolls-Royce responded by opening a new factory in Springfield, Massachusetts, in the United States in 1921 and introduced a smaller, more affordable Model Twenty in 1922.

The Springfield plant allowed Rolls-Royce to meet the overwhelming demand for its product in the U.S., and during its ten years of operation would build 1,703 Ghosts and 1,241 Phantoms. A total of 2,944 vehicles were built by the U.S.-based Rolls-Royce factory before it closed in 1931.

The Rolls-Royce Twenty
Built between 1922 and 1929, the Twenty (codenamed the Goshawk) complemented its (primarily) chauffer-driven Silver Ghost sibling by appealing to the owner-driver market. While the Silver Ghost employed a 453.3 cubic-inch (7428cc) straight-6 engine and a 143.5-inch wheelbase platform (a 144- and 150.5-inch wheelbase was available from 1923 onward), the Twenty used a 190.8 (3,127cc) straight-6 engine (cast in one block with detachable cylinder heads) and a 128.9-inch wheelbase. The ladder frame chassis was equipped with all-round semi-elliptic leaf-sprung suspension, rear-wheel brakes and a fully floating 'Hotchkiss Drive' back axle.

The Twenty proved popular and a remarkable success during this period of economic uncertainty, becoming the first in a line of smaller models built alongside the Silver Ghost and Phantoms in the period leading up to the Second World War. The total production reached 2,885 (as many as 2,940) examples before its replacement, the 20/25, was launched in 1929.

The Rolls-Royce 20/25
The performance of the Twenty suffered due to heavy formal coachwork, prompting Rolls-Royce to introduce a replacement in 1929, designated the 20/25. By increasing the bore (from 3 to 3.25 inches; the stroke remained unchanged), Rolls-Royce's engineers raised the engine capacity to 3.7-litres (3,675cc), improving both power output and torque. The RAC rating was now 25.4 hp.

The 3,699cc inline 6-cylinder engine had overhead pushrod operated valves and a separate cast iron block and aluminum crankcase with detachable cast iron 6-plug head. It had a seven-bearing crankshaft, a pressure-fed lubrication system with relief valve feeding timing gears and rocker shaft, and an independent coil ignition system and standby magnetos. The carburetor was a single Rolls-Royce 2-jet type unit. By 1930, the compression ratio was 5.25:1, and in 1932, compression rose to 7.75:1, and a high-lift camshaft was installed. The transmission was a four-speed gearbox with synchromesh in 3rd and 4th gear from 1932. It used a single dry plate clutch (Borg & Beck clutch from 1936 forward) and open drive propeller shaft (Hypoid rear axle in 1936). Stopping power was via internal expanding four-wheel brakes with an independent handbrake on the rear wheels. The steering was via a worm and nut system through 1936, when it was replaced with a Marles cam & roller steering setup.

1934 Rolls-Royce 20 / 25 HP photo
Coupe
Additional mechanical improvements included four-wheel braking with a servo and an independent handbrake, while later models gained an all-synchromesh gearbox and Borg and Beck clutch. The semi-elliptic suspension of its predecessor was retained but featured pedal-operated 'one-shot' Bijur centralized lubrication, and by 1932, it used a completely centralized chassis lubrication system. Wheelbase lengths now measured 129- or 132-inches, with the longer frame soon standardized after production commenced.

The 20/25 wore a wide range of coachwork as each was built to individual order, from formal limousines to open tourers. Among the coachbuilders who created coachwork for the 20/25 include Park Ward, Carlton, Hooper, Mulliner, and Thrupp & Maberly.

The 20/25 was the most popular Rolls-Royce model built between the wars, with 3,824 (as many as 3,827) produced by 1936. Most (approximately 93%) of the 20/25 models were sold within the United Kingdom. The 25/30 was replaced in 1938 by the Wraith, which used a new chassis and an independent front suspension.

1934 Rolls-Royce 20 / 25 HP photo
Sport Saloon by Freestone & Webb
Chassis #: GYD 42
View info and history
Auction entries : 1
Rolls-Royce introduced the 20/25 model in 1929 at the Olympia Motor Show and its popularity allowed the company to acquire Bentley Motors Ltd. in 1931. Since the Bentley 8-Litre car encroached on Phantom II territory, its production was discontinued. This meant Bentley had no product to produce, but they did have engineers, manufacturing employees, and brand recognition. With these resources, Rolls-Royce created a new Bentley using the 20/25 engine as a basis along with a chassis intended for the 2 ¾ litre Rolls-Royce - a stillborn automobile meant as an even more economically friendly version of the 20/25. This combination birthed the first Derby Bentley - the 3 ½ litre Bentley - soon to be known as the 'Silent Sports Car.'

The Rolls-Royce 25/30
The Rolls-Royce 25/30 was produced from 1936 to 1938, with 1,201 examples built. Their 4,257cc inline 6-cylinder engine, similar to the 20/25 engine, had a 6:1 compression ratio and a single proprietary Stromberg downdraught carburetor. Producing more power than its 20/25 sibling, the 25/30 was capable of more gracefully carrying the elaborate coachwork being requested by customers.

The 25/30 used the 132-inch wheelbase riveted chassis of the 20/25 with rigid axles suspended by half-elliptic springs with hydraulic dampers. Mechanical four-wheel brakes used under license of Hispano-Suiza provided the stopping power. Coachwork was created by H.J. Mulliner & Company, Arthur Mulliner, Hooper, Park Ward, and Thrupp & Maberly.

The Wraith (Prewar)
Between 1938 and 1939, Rolls-Royce produced a model dubbed the Wraith which was a Scottish word meaning 'ghost' or 'spirit.' The 136-inch wheelbase was powered by a 4,257cc straight-6 engine coupled to a four-speed gearbox with synchromesh on second through fourth gears. The engine was based on the 25/30 engine but with a cross-flow cylinder head. The suspension was independent with semi-elliptical leaf springs on the rear axle. Rather than using the traditional riveted construction techniques, the chassis were now welded. Mechanical servo-driven drum brakes patented by Hispano-Suiza were built by Rolls-Royce under license.

1934 Rolls-Royce 20 / 25 HP photo
Saloon by Mulliner
View info and history
A total of 491 examples were built before production ended due to growing instability and threats of war.

The Silver Wraith (Postwar)
When World War II came to a close, Rolls-Royce resumed automobile production with the Silver Wraith, produced from 1946 to 1958 alongside the shorter Bentley Mark VI. Initially, a 127-inch wheelbase chassis was used, growing to 133 inches in 1951. A 260 cubic-inch (4.3 L) engine provided the power, increasing in 1951 to 278.6 cubic-inches (4,566cc) and in 1955 to 298.2 CID (4,887cc).

During its production lifespan, a total of 1,883 examples of the Silver Wraith were built.


by Daniel Vaughan | Mar 2023

Related Reading : Rolls-Royce 20/25HP History

Rolls-Royce introduced the replacement for the Twenty in 1929, dubbed the 2025 HP, and utilized the chassis of its predecessor. The engine was enlarged from 3.1 liters to 3.7 liters, giving a significant increase in performance. Improved power had become a necessity because owners often insisted on fitting elaborate and heavy coachwork, which severely affected the performance. This was an important....
Continue Reading >>

1934 Rolls-Royce 20 / 25 HP Vehicle Profiles

1934 Rolls-Royce 20 / 25 HP vehicle information
Sedanca Coupe

Coachwork: Barker
Chassis #: GAF21
Engine #: V7A
1934 Rolls-Royce 20 / 25 HP vehicle information
3 Position Sedanca Drop Head Coupe

Coachwork: Mulliner
Chassis #: GXB45
1934 Rolls-Royce 20 / 25 HP vehicle information
Tourer

Coachwork: Barker
Chassis #: GXB8
1934 Rolls-Royce 20 / 25 HP vehicle information
Fastback

Designer: Park Ward
1934 Rolls-Royce 20 / 25 HP vehicle information
Sport Saloon

Coachwork: Freestone & Webb
Chassis #: GYD 42
1934 Rolls-Royce 20 / 25 HP vehicle information
Sedanca Coupe

Coachwork: Gurney Nutting
Chassis #: GAF29
Engine #: BXA 868
1934 Rolls-Royce 20 / 25 HP vehicle information
Saloon

Coachwork: Mulliner

Recent Vehicle Additions

Performance and Specification Comparison

20/25HP

Specification Comparison by Year

Year
Production
Wheelbase
Engine
Prices
132.00 in.
6 cyl., 223.90 CID., 25.00hp
129.00 in.
6 cyl., 224.57 CID., 100.00hp
129.00 in., 132.00 in.
6 cyl., 223.90 CID., 25.00hp
132.00 in.
6 cyl., 223.90 CID., 75.00hp
129.00 in., 131.90 in., 132.00 in.
6 cyl., 225.73 CID., 27.00hp
129.00 in., 132.00 in.
6 cyl., 224.57 CID., 25.00hp

Related Automotive News

Magnificent Mercedes-Benz 540K wins Best of Show at Salon Privé Concours d'Elégance

Magnificent Mercedes-Benz 540K wins Best of Show at Salon Privé Concours d'Elégance

1938 Mercedes-Benz 540 K Cabriolet A Singelfenden wins top award at Salon Privé Unique low-drag Lightweight tops Jaguar E-type class Monte-Carlo Rally Aston Martin DB2 scoops two awards Superb entry spanned everything from veteran machinery to s...
From pioneers to performance greats: Salon Privé unveils stellar entry for Concours d'Elégance

From pioneers to performance greats: Salon Privé unveils stellar entry for Concours d'Elégance

More than 100 years of motoring history on show at Blenheim Palace Awards will be decided by ICJAG panel of world-leading experts and chief automotive designers Coachbuilt beauties entered, along with competition legends on two wheels and four Cl...
Fearsome and Solidly Original 1971 Hemi Challenger a Feature at Russo and Steele's Scottsdale Auction Event

Fearsome and Solidly Original 1971 Hemi Challenger a Feature at Russo and Steele's Scottsdale Auction Event

Scottsdale, Arizona (January 3rd, 2017) – The Chrysler E-bodies might have been the last to enter Detroits pony car game. Though critics argue that the best were saved for last with these cars, making their introduction more than five years after...
Lancia Named 2016 Best of Show

Lancia Named 2016 Best of Show

PEBBLE BEACH, Calif. (August 21, 2016) — The 2016 Pebble Beach Concours dElegance concluded with first-time entrant Richard Mattei lifting the top prize high overhead soon after his 1936 Lancia Astura Pinin Farina Cabriolet was named Best of...
Barrett-Jackson Flavors Its January Scottsdale Auction With NASCAR Treats

Barrett-Jackson Flavors Its January Scottsdale Auction With NASCAR Treats

RACING HERITAGE, HIGH PERFORMANCE ARE RECIPES FOR CAR-COLLECTING FEAST SPEED™ SET FOR 39 HOURS of LIVE COVERAGE STARTING JAN. 15 The great Henry Ford once said, Auto racing began five minutes after the second car was built. ...