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Model guide

Jaguar SS 100: the pre-war sports car that named the marque (1936-1939)

Part of: Classic Jaguar, the full marque guide
At a glance
Years
1936-1939
Body styles
Two-seat open sports
Drivetrain
Front engine, rear-wheel drive
Engines
2.5 and 3.5-litre overhead-valve six
Power
Around 100 bhp to 125 bhp
Top speed
Around 95 mph; the 3.5-litre cars reached 100 mph
Production
Around 300
Assembly
Coventry
Designer
William Lyons
Values
Among the most valuable pre-war British sports cars; genuine 3.5-litre cars reach well into six figures. Many replicas exist at a fraction of the price
The name
Among the first cars to carry the Jaguar name, from 1935-36
Caution
Replicas are common; provenance is everything on a genuine car

Before there was a Jaguar company, there was the SS 100, and it already had the Jaguar name. William Lyons’ pre-war sports car was a short, low, fast open two-seater that looked and went like cars costing far more, and it is the car in which the whole Jaguar story, value, beauty and speed for the money, first came fully together.

A silver SS Jaguar 100 racing on a circuit, front three-quarter view, race number 100
An SS Jaguar 100 in historic competition. Short, low and fast, it gave William Lyons' young marque the glamour he wanted.Photo by Dave Hamster / CC BY 2.0

William Lyons and the SS years

Lyons’ firm grew out of the Swallow Sidecar Company and moved through the early 1930s from coachbuilt bodies into cars of its own, the SS1 and SS2. These were striking, low-slung machines sold at prices that undercut anything that looked as expensive. By the mid-1930s the company, now SS Cars, was ready to put its name to something faster and more focused.

The thread running through all of it was Lyons himself, a proprietor with an extraordinary eye for line and value who styled his cars by judging full-size mock-ups. The promise was always the same: a car that looked like money and cost much less. The SS 100 made that promise sporting.

A maroon SS Jaguar tourer at a show, front three-quarter view
An early SS Jaguar. Lyons moved from coachbuilding and the rakish SS1 into handsome cars sold for far less than they looked worth.Photo by Dave Hamster / CC BY 2.0

The SS 100

Launched in 1936, the SS 100 put a shortened chassis under a minimal, elegant two-seat body, with cycle-style wings, a low stance and an overhead-valve six-cylinder engine developed with the help of the gas-flow specialist Harry Weslake. In 2.5-litre form it was quick; in the 3.5-litre form of 1938 it could reach the 100 mph its name promised, a genuinely fast car for the money.

It was never built in large numbers, around 300 in total, and it was as much a flagship and a competition car as a volume product. It rallied and raced with success, and it gave the young marque exactly the glamorous, fast image Lyons wanted. Today it is among the most desirable pre-war British sports cars of all.

A silver SS Jaguar 100 open sports car in profile at a show
The SS 100's minimal two-seat body. In 3.5-litre form it could reach the 100 mph its name promised.Photo by Dave Hamster / CC BY 2.0

The SS Jaguar saloons

Alongside the sports car came the cars that carried the volume. The SS Jaguar saloons, introduced in 1935 and 1936, were handsome, well-appointed four-doors with the same six-cylinder engines, and they undercut their rivals so heavily on price that buyers struggled to believe the figures. They established the saloon side of the business that, after the war, produced the Mark V and the cars that followed.

Both the saloons and the SS 100 shared the formula and the new name. It was here, in the late 1930s, that “Jaguar” first came to mean a fast, beautiful car sold for less than it looked worth.

A dark green SS Jaguar 2.5-litre saloon of 1939 on grass, front three-quarter view, UK registration BUT 7
An SS Jaguar saloon. Handsome and well-appointed, it undercut its rivals so heavily that buyers struggled to believe the price.Photo by kitmasterbloke / CC BY 2.0

From SS to Jaguar

The Jaguar name was a model name through the late 1930s; the company was still SS Cars. After the Second World War the SS initials carried an obvious and unwelcome association, and in 1945 the shareholders renamed the business Jaguar Cars after its best-known model. The SS 100 and the SS Jaguar saloons are therefore early Jaguars in everything but the badge on the building, the direct ancestors of the XK120 and everything that came after.

A grey SS Jaguar 2.5-litre saloon of 1937, rear three-quarter view at a show
These late-1930s cars are early Jaguars in all but the company name, the direct ancestors of the post-war saloons.Photo by Andrew Bone / CC BY 2.0

Owning and buying: genuine versus replica

This is a car where the first question is authenticity. Genuine SS 100s are rare and extremely valuable, and the shape has been recreated many times on various chassis, so a buyer must establish beyond doubt that a car is real, with the correct chassis, running gear and a documented history. Expert verification is essential at this level.

A genuine car is a serious pre-war machine to own, demanding the techniques and maintenance of its era and the support of the marque’s specialists, much of it the wider business of running a classic car taken to its most rarefied. For most enthusiasts the SS 100 is a car to admire at events rather than to buy, which is part of its mystique.

A dark SS Jaguar 100 with its bonnet open, showing the six-cylinder engine
On a car this rare and valuable, provenance is everything: a genuine SS 100 has the correct chassis, running gear and documented history.Photo by Rutger van der Maar / CC BY 2.0

Value and where it sits

A genuine SS 100 is a six-figure classic, the best original 3.5-litre cars reaching well beyond, while replicas sell for a small fraction and should never be mistaken for the real thing. It is the pre-war jewel of the Jaguar story and one of the defining British sports cars of the 1930s, the car in which the marque found its voice.

A red SS Jaguar 100 open sports car, rear three-quarter view, UK registration ERB 290
A genuine SS 100 is a six-figure classic; only around 300 were built before the war.Photo by Andrew Bone / CC BY 2.0

More photos

Quick answers

Frequently asked questions

What is the SS Jaguar 100?
The SS 100 is a pre-war open sports car built by SS Cars, William Lyons' Coventry company, from 1936 to 1939. It was a short, low, purposeful two-seater on a shortened saloon chassis, with an overhead-valve six-cylinder engine, and it carried the Jaguar name that the firm had first used in 1935. Only around 300 were built, and it is now one of the most prized pre-war British sports cars.
Did the SS 100 really do 100 mph?
The 3.5-litre version did. Its name was a claim that the car could reach 100 mph, and in 3.5-litre form, introduced in 1938, it genuinely could, which was a remarkable figure for an affordable sports car of the late 1930s. The earlier and more common 2.5-litre cars were a little slower but still quick for their day. As with everything Lyons built, the SS 100 delivered performance and presence far beyond its price.
How is the SS 100 connected to Jaguar?
Directly. SS Cars used the Jaguar name first as a model name, on the SS Jaguar saloons and the SS 100 from 1935-36, while the company itself was still called SS Cars. After the Second World War the SS initials carried an unwelcome association, and in 1945 the firm renamed itself Jaguar Cars after its best-known model. So the SS 100 is, in effect, an early Jaguar in all but company name.
Are most SS 100s replicas?
Many cars presented as SS 100s are replicas or recreations, because genuine cars are rare and extremely valuable, and the shape has been reproduced on various chassis over the years. A real SS 100 has documented history and the correct chassis and running gear, and commands a vast premium over a replica. On a car at this level, provenance and expert verification matter more than almost anything.
How much is an SS Jaguar 100 worth?
A genuine SS 100 is a six-figure classic, with the best original 3.5-litre cars reaching well beyond that at auction. Replicas and recreations sell for a small fraction of the price and should never be confused with the real thing. As ever with the rarest cars, condition, originality and a watertight history drive the value, and buying needs specialist advice.
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