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The Invicta Car Company has adopted several innovative approaches in both the design and construction phases of manufacturing its first car in modern times. The overall appearance and the engineering layout of the S1 are the collaborative results of a three-way think-tank between Invicta Chairman Michael Bristow, project manager Chris Marsh and consultant designer Leigh Adams.

Invicta has worked in secrecy for 24 months because it wanted to show the public what it had achieved – not what it hoped to achieve. So, the new S1 revealed at the Motor Show is not a concept car, it is a full production model, ready to run and customers can place orders now – confident that the first cars will be delivered early in 2003.

A thoroughly modern car, the new Invicta S1 embodies the standards, quality and spirit behind the 1930’s Invicta cars – aiming to provide today’s enthusiast motorists with an exceptionally rewarding driving and ownership experience, matching the marque’s original promise to deliver “the most wonderful performance in the world”.

Design & Construction
The Invicta S1 is the world’s first car to feature a one-piece carbon-fibre bodyshell. This shell, when bonded to the steel tube spaceframe chassis, creates an immensely strong, but lightweight, structure and results in a car with high flexional and torsional rigidity (for responsive handling) and excellent impact resistance (for high levels of occupant safety).

Crucial to the successful building of the one-piece bodyshell was the decision to manufacture much of it in a new carbon fibre material from the Advanced Composites Group, called ZPREG. This revolutionary material weighs just 30% of the equivalent steel panel and is much faster and easier to work with than conventional carbon fibre. It also gives an ‘A Class’ surface to accept a top-quality paint finish, makes use of composite tooling which can be produced in under 12 weeks, and does not require the use of an autoclave or the high laminator skills typical of previous carbon fibre manufacturing in the motorsport and aerospace industries.

The spaceframe chassis is more conventional and incorporates all the ‘best practice’ features of this well established construction method. It weighs 160 kilos, but all of that weight is low down, below the car’s roll centre. Made from 2mm thick steel formed into 40mm square tubes and cross-braced for maximum strength, the chassis construction uses TIG welding to give a smooth surface in the areas that are bonded to the bodyshell.

Engine & Performance
Fundamental to Invicta’s desire to deliver no-compromise performance in terms of handling balance and sheer speed, was the decision to mount the S1’s engine and gearbox well back in the chassis and the 100-litre fuel tank transversely between the rear wheels, to achieve close to the ideal 50/50 front/rear weight distribution.

Fitted with Invicta’s own air-intake and exhaust systems, the 4.6-litre engine powering the S1 is supplied by Ford’s Special Vehicle Team (SVT) in America. The all-aluminium, 32-valve V8 weighs just 240 kilos and produces 320 bhp and 300 lb ft of torque. Light, smooth-revving and ultra-reliable, this engine promises to deliver stunning acceleration in the 1100 kg S1 – which is more than 300 kg lighter than the Ford Mustang Cobra which uses the same engine in the USA. Each engine is hand-built at Ford’s SVT facility and carries a plaque signed by the two technicians responsible for its assembly.

The completely flat floor of the S1 and the rising rear undertray promise to give low-drag and generate downforce. Calculations predict that the S1 will accelerate from 0-to-60 mph in five seconds, to 100 mph in under 11 seconds, and will comfortably exceed 170 mph when road conditions permit. The combination of high power, massive torque and low weight is a recipe for good fuel economy and Invicta calculates that the S1 will return 25 mpg overall, giving a comfortable 500 mile range from the 21.9 gallon (100-litre) fuel tank.

Text and photos: Invicta Car Company

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