Triumph Slant-4 engine
Encyclopedia
Engine
An engine or motor is a machine designed to convert energy into useful mechanical motion. Heat engines, including internal combustion engines and external combustion engines burn a fuel to create heat which is then used to create motion...
developed by Triumph
Triumph Motor Company
The Triumph Motor Company was a British car and motor manufacturing company. The Triumph marque is owned currently by BMW. The marque had its origins in 1885 when Siegfried Bettmann of Nuremberg initiated S. Bettmann & Co and started importing bicycles from Europe and selling them with his own...
. According to Triumph historians Graham Robson and Richard Langworth in Triumph Cars, the complete story, the engine was developed in-house by a design team led by Lewis Dawtry and Harry Webster.
The UK engineering and consultancy company Ricardo
Harry Ricardo
Sir Harry Ricardo was one of the foremost engine designers and researchers in the early years of the development of the internal combustion engine....
, which did have a general engine-development contract with Triumph, was not directly involved with its design, but was usually kept informed of anything new being planned. Ricardo was involved in developing a new engine for Saab
Saab Automobile
Saab Automobile AB, better known as Saab , is a Swedish car manufacturer owned by Dutch automobile manufacturer Swedish Automobile NV, formerly Spyker Cars NV. It is the exclusive automobile Royal Warrant holder as appointed by the King of Sweden...
, for use in their new 99
Saab 99
- Development :On April 2, 1965, Gudmund's day in Sweden, after several years of planning, the Saab board started Project Gudmund. This was a project to develop a new and larger car to take the manufacturer beyond the market for the smaller Saab 96...
model. When that development proved too expensive and risky to produce, Ricardo, knowing the slant-4 was almost ready for production, brought Saab into contact with Triumph.
Saab first used the Triumph Slant-4 at 1.7 L (1709 cc) for the Saab 99
Saab 99
- Development :On April 2, 1965, Gudmund's day in Sweden, after several years of planning, the Saab board started Project Gudmund. This was a project to develop a new and larger car to take the manufacturer beyond the market for the smaller Saab 96...
. Only later, as production capacity increased, did it become available in Triumphs. Development by Saab continued into the 1990s. The engine is a straight-4
Straight-4
The inline-four engine or straight-four engine is an internal combustion engine with all four cylinders mounted in a straight line, or plane along the crankcase. The single bank of cylinders may be oriented in either a vertical or an inclined plane with all the pistons driving a common crankshaft....
with the cylinders tilted at 45 degrees (actually in effect half of the Triumph V8
Triumph V8
The Triumph V8 is a 3.0 litre V8 developed in house by Triumph for the Triumph Stag. This was basically two Triumph Slant-4 engines 'stuck' together. It consisted of a single overhead cam cast iron block with aluminium heads.-Development:...
that was used in the Triumph Stag
Triumph Stag
The Triumph Stag is a British car that was sold between 1970 and 1978 by the Triumph Motor Company, styled by the Italian designer Giovanni Michelotti.-Design and styling:...
).
The engine was used by Triumph in the Dolomite
Triumph Dolomite
The Triumph Dolomite was a popular small saloon car produced by the Triumph Motor Company division of the British Leyland Corporation in Canley, Coventry between October 1972 and August 1980.-History:...
1850, the Dolomite Sprint, and the TR7
Triumph TR7
The Triumph TR7 is a sports car manufactured from September 1974 to October 1981 by the Triumph Motor Company in the United Kingdom. It was initially produced at the Speke, Liverpool factory, moving to Canley, Coventry in 1978 and then finally to the Rover plant in Solihull in 1980...
. It was also used by Panther
Panther Westwinds
Panther Westwinds was a manufacturer of niche sports cars and luxury cars, based in Surrey, United Kingdom. Founded in 1972 by Robert Jankel, the Panther company enjoyed success throughout the 1970s with retro-styled cars based on the mechanical components of standard production cars from other...
in the Dolomite-based Rio
Panther Rio
The Panther Rio was a motor car made by British manufacturer Panther Westwinds, using Triumph Dolomite mechanicals. According to the company, it differed from the family saloon-class Dolomite, in being finished to "Rolls-Royce standards". Only 38 were built between 1975 and 1977...
(1975–1977). Triumph ended manufacture of the engine when the TR7 was discontinued in 1981.
Sprint version
Triumph added unique SOHC 4-valveMulti-valve
In automotive engineering a multi-valve or multivalve engine is one where each cylinder has more than two valves. A multi-valve engine has better breathing and can operate at higher revolutions per minute than a two-valve engine, delivering more power.- Multi-valve rationale :A multi-valve design...
cylinder heads to the Slant-4 for 1973's Dolomite Sprint
Triumph Dolomite
The Triumph Dolomite was a popular small saloon car produced by the Triumph Motor Company division of the British Leyland Corporation in Canley, Coventry between October 1972 and August 1980.-History:...
. This is regarded as the first mass-produced multi-valve
Multi-valve
In automotive engineering a multi-valve or multivalve engine is one where each cylinder has more than two valves. A multi-valve engine has better breathing and can operate at higher revolutions per minute than a two-valve engine, delivering more power.- Multi-valve rationale :A multi-valve design...
car engine.
Saab B engine
Saab later increased the engine size to 1.85 L and in 1972 the company brought production in-house (to Scania) for the 2.0 L B versionSaab B engine
The Saab B engine is based on the Triumph Slant-4 engine and replaced their aging two-stroke engine. When it was decided to develop a new Saab model in 1964, the Saab 99, the decision was also made to give it a modern four-stroke engine. A contract was signed with Triumph to deliver their soon to...
. This engine shared much with the original Triumph design, including bore centers and bearings, but was substantially redesigned. The Saab B engine was replaced by the related Saab H engine
Saab H engine
The Saab H engine is a redesign of the Saab B engine. Despite the name it is not an H engine, but a slanted inline-4. The H engine was introduced in 1981 in the Saab 900 and was also used in the Saab 99 from 1982 onwards and the Saab 90. It continued in use in the 900/9-3, 9000, and 9-5...
.