Cumberford Martinique - AllCarIndex

From the official Cumberford Martinique brochure issued in 1981:

Text may not be reused without full credit to www.allcarindex.com and direct link to this webpage.

CUMBERFORD MARTINIQUE

The shape strikes you first, of course.

Low, wide, powerfully thrusting and elegantly balanced on its glistening, geometrically-pure alloy wheels, the shape evokes the pleasures of a time long ago, a time when roads were emptier, when driving was an adventure, when open roadsters were the highest expression of the coachbuilders' art.

Yet there can be no mistaking this car for the creation of another era. If its lines speak of glories past, its proportions subtly tell you that this is a thoroughly modem design. The length of the cockpit, the reduced diameter of the hand-made steering wheel, the tell-tale marker lamps and outside mirrors are details you expect to find on cars of the 80's. And if you look more carefully, more critically, you become aware that there are no asperities, no pro-tuberances, no wind-scooping fenders... indeed, to the practiced eye the long hours of wind tunnel refinement are readily apparent, as much for what is absent as for what is there.

There are no extraneous trumpet horns, no dummy ex-haust pipes, no free-standing ornaments. The lines of the Martinique are pure and purposeful... even inevitable, if one accepts the premise that to be valid today even classical styling must be joined to low aerodynamic drag and positive stability at speed.

Speed there is: this is no boulevard pretender to credentials not possessed. The Martinique was designed for hard driving on the tightest mountain roads, and for exhilarating flat-out runs across Middle Europe where there are no speed limits and where only the toughest cars can survive hour after hour of full performance. Yet it is not a noisy exotic in which all comfort has been sacrificed to a brilliant highway performance. The Martinque's driver sits comfortably upright in a luxuriously-trimmed seat and gently caresses the fully-powered controls which give mastery over one of the most advanced chassis ever offered for a road car. allcarindex

CHASSIS

On an immensely strong platform of solid cast aluminum the Martinique's designers have mounted an extraordinary powered hydraulic-pneumatic suspension system which combines the best of aeronautical practice with racing-car geometric accuracy. The suspension elements, mounted on precision roller bearings, are tough - perhaps the toughest offered on a road car anywhere in the world - but they are also very light: forged steel and pressure-cast aluminum parts pared down to their purest essentials. And that lightness gives the Martinique a combination of ultra-soft ride and ultra-solid roadholding that is unique in high performance sports cars today.

With the mass of its engine carried well within its wheelbase, the Martinique has a low polar moment of in-ertia, just as do modern racing cars, giving quick response to control inputs. The Martinique may be the only luxury car which can give a good account of itself at a gymkhana, and it is, certainly the only one with quick-ratio steering able to tailor its power assistance in proportion to road speed. At parking speeds, steering is feather-light, and is arranged to bring itself back to the straight-ahead position without driver effort. As road speed increases, the power assist decreases in so unobtrusive a way that the driver is hardly aware that there has been a change; he knows only that it is utterly precise and absolutely predictable, the steering of a true thoroughbred.

The brakes are powered, too. Not in the sense, however, of those "power brakes" which are nothing more than ordinary hydraulic brakes with a vacuum-can servomechanism to help the driver push harder on a master cylinder, as found in most ordinary cars. In the Martinique the force for stopping is supplied by a tiny hydraulic pump, not much bigger than your own heart but 175 times more powerful, which charges a pressure accumulator. Your foot presses gently upon a pedal which controls a valve to meter some of that high pressure to the brake pads at the front, slowing the car as you will. But the rear brakes are not controlled so directly by the driver. Rather, the rear suspension system senses the load on the rear tires, and safely modulates the pressure according to the amount of traction available.

With the huge Michelin TRX tires - a size specially made for the Martinique and used on no other car - there is plenty of traction. These tires represent the leading edge of modern tire technology, with a combination of steel and Kevlar belts used in their radial construction, for tread stiffness, and Kevlar used alone in the sidewalls for a supple and compliant ride. And if comfort and control are of primary interest, performance is not forgotten.

With a VR rating, these tires can safely be run at more than 130 miles per hour without undue heat build-up. The tires are mounted on Cumberford-designed aluminum wheels which enhance the car's aerodynamic qualities as well as its appearance, and which have been tested to surpass every industry standard.

The cast aluminum chassis is perhaps no more than the skeleton of the Martinique, but it is a beautiful object in its own right. Made of precisely-machined modular castings, the chassis is also the external shell of the passenger compartment, providing a level of safety which can only be attained by careful original design. There is no other Chassis which could meet Cumberford Corporation's requirements for the Martinique, and there is no other chassis more precise in its alignment: plus or minus ten thousandths of an inch!

To attain such a standard, and to maintain it in service, exceptional measures are called for in assembly. Costly American aerospace fasteners, designed so that they can only be installed perfectly, without the possibility of human error compromising their strength, are used to join the castings. These metallurgical marvels, worth their weight in precious metals, are indicative of the exceptional care with which the Martinique is engineered and built.

If the fasteners - the aircraft industry calls them "pins and collars" because "bolts and nuts" simply cannot convey an adequate sense of their precision and perfection - are inspiring by themselves, their manner of installation in the Martinique chassis is reassuring. Although each pin and collar is coated with a Military Specification anti-corrosion coating, they are all dipped in a zinc- chromate solution at the time of assembly and put together wet. Not a molecule of corrosive atmosphere or road salt can penetrate a chassis joint. The Martinique chassis is designed to last for years with the minimum of special care, no matter how much it may be driven. After assembly, the entire chassis is painted with a catalyzed two-part paint system which-is used by the U.S. Navy and U.S. Coast Guard to protect aluminum warships in the highly-corrosive atmosphere at sea. allcarindex

BODY CONSTRUCTION

The body of the Martinique is all aluminum, with unstressed sheet panels attached to the load-bearing castings which make up the principal structure. The same exceptional care with respect to corrosion treatment which is given to the chassis is carried over to the body as well: every fastener is wet-installed and fully- protected. The final paint is a polyurethane system used by many of America's leading airlines to protect their multi-million dollar aircraft. It has the flexibility to withstand the sudden sharp temperature changes to which such aircraft are routinely subjected, and the toughness to resist hailstones and raindrops struck at 600 miles per hour.

The Martinique's doors are a model of the sort of care used in designing the entire body. They are framed with heat-treated castings and wrought-alloy side-impact bars, skinned with aircraft-grade aluminum sheet, and are fitted with the finest hardware elements available: tough Swedish steel for the hinges, the best German pin-guide door latches and locks, and powerful American window lift mechanisms. They are covered with tough Thai water-buffalo hide. Their hand-finished cappings are of African mahogany, accented with American maple. They close with a solid sound, and they will stay solid... those aerospace fasteners assure it.

The hood is made in three separate parts: the central cover which opens for routine maintenance, and side panels which are removable for access to the long-life sealed battery and to the suspension spheres. The hood is hinged at the front for convenience and safety, and is held at the rear by two positive-action toggle latches, operated by the driver manually. It does not close against a spring, and thus never need be slammed.

The one-piece top-well cover is mounted on stainless- steel hinges which are linked to gas springs deep within the rear body. These assure that there is no need to slam this panel, either. Graceful wooden fairings protect the hinge mechanisms from the weather. The elegant wood- and-alloy-framed folding top was specially designed and developed for the Martinique, and was shaped in the wind tunnel to minimize aerodynamic drag and so aerodynamic noise.

The rear bodywork is designed to crumple in a high-speed rear impact, and thereby absorb energy. The fuel tank is carried ahead of the massive transverse cross-members to which the rear suspension is mounted, and is exceptionally well-protected. The unique Martinique fuel filling mechanism is surely the most original and most convenient to come into use since the demise of six-inch diameter quick-action racing-car gas caps of the 1930's. It protects the car's paintwork, meets all safety regulations, and although not locked, can not be opened unless the driver wishes it to be, at which point it rises above the body surface to meet the fuel nozzle. allcarindex

FENDERS

The gleaming yacht-finished wooden fenders of the Mar-tinique give it its stamp of identity, and perhaps their esthetic value would be enough to justify their presence. But there is more than wood to the Martinique’s fender construction, just as there is more than beauty to justify the complex process of creating these sculptural objects. Wood is strikingly beautiful, of course, and each piece of it is individual and unique. No two Martiniques will ever be exactly alike, because the natural colors, warmth of tone and delicate decorative tracery of grain and ray must differ on each car. Wood cannot be worked by automation; it is a living material and can only attain its full beauty if a knowing craftsman selects and shapes and finishes it. Wood is also one of the finest structural materials known to mankind, and it provides a resilient, stiff surface to the fender. Beneath that surface is a space- age sandwich laminate made of tougher-than-steel Kevlar fabric locally reinforced with carbon fibers stabilized by a core of Klegecell, a rigid plastic foam used in advanced aircraft structures. The real point of all this has to do with engineering: the designers want to concentrate all weight as close to the center of the car as possible. The fenders must be light if handling is not to be compromised, and they must be tough if the owner is to enjoy their beauty without worrying about their being delicate. So they weigh only 22 pounds, for the front fenders, and 14 pounds for the rear ones, and they are able to take abuse. If a dump truck caves one in, it can be unbolted and replaced in a matter of minutes, and the craftsmen who made it will carefully and lovingly repair it, just as they would repair a wooden yacht, a wooden airplane, or a musical instrument. And of course those who prefer a more traditional look can order their fenders painted in the color of their choice, without the mahogany veneer surface. An additional stiffening layer of Kevlar replaces it, and a paint stripe runs along the peak. allcarindex

COCKPIT

The Martinique's cockpit is arranged for sporting driving: the seats are as close to the centerline of the car as possible, to give the driver the optimum viewpoint. And the cockpit is shaped rather like the human body; it is narrow at the ankles, wider at the seat, and widest at the shoulders. There is enough room, but no more; it is wasteful to carry structural weight where it is not needed. The cockpit is trimmed and framed with beautifully handworked solid wood, and is upholstered entirely in leather. The carpeting is wool, of course, with a solid backing of natural fibers. Because the car is a serious road machine, no attempt has been made to clutter the instrument panel with useless gauges. Rather, everything has been simplified as far as possible. Warning lights are used - as they are in all NASA spacecraft - because they do the job better than gauges can. There is a speedometer, a fuel contents gauge, a temperature gauge and a tachometer. That's all. That's all you need.

ENGINE

The heart of any car is its engine. Ultimately the judgements of historians about any of the great cars have been based upon the character of their engines as much as upon anything else. It would have been easy to have made the Martinique very fast by installing a burly V-8, but at what cost to character! The Martinique is not meant merely to be fast; it is meant to be swift, which is another matter entirely. And it is meant to be smooth, soothing and restful and refined with it. The best engine configuration, indeed virtually the only engine configuration which will give those virtues, is the inline six cylinder. And of all the world's inline sixes, surely none is so respected today as the BMW.

BMW stands for Bavarian Motor Works, and that highly successful company is one which has never forgotten that "Motor" is its middle name. Every BMW engine, whether it be for a motorcycle, an economy car or an upper-class luxury model is the product of the company's aircraft engine heritage, and every one of them is a superior product. When BMW recently decided to enter the world of Formula One racing, they did not bother to design an all-new specialized racing engine, as all their rivals have done. Rather, they are using production cylinder blocks. Not just blocks made specially from production tooling; no, they are using engines taken from used cars which have already had at least 60,000 miles of road use! They say that the blocks are nicely "seasoned" then and are good for extracting five or six times the original power output.

The big-block, 3.2 liter six cylinder used in the Cumber- ford Martinique is working well within its limits when it is tuned to produce 174 horsepower; in Europe it gives 197, and variations of it have been taken up to more than 800 horsepower by turbocharging. It is not unusual for these engines to do 200,000 miles without bottom-end overhaul, even in cars driven very hard. With the light weight of the Martinique, and with the cushioning effect of the ZF automatic transmission, the engine is very lightly worked, and should enjoy a very long life. Naturally, the Martinique's engine meets all of the most stringent U.S. anti-pollution requirements, and it runs on ordinary lead-free 91 octane fuel without problem. allcarindex

SERVICE AND MAINTENANCE

Cumberford owners receive prompt service at designated service points. A 24-hour toll-free telephone service will bring immediate attention in the event of emergency. All parts are held in stock at the factory, and will be available, following motor industry custom, for a ten year period from the date of production.

COLORS

Owners may choose from a number of color combinations selected by the Cumberford design staff to enhance the mahogany fenders and trim:

Brown over Beige

Maroon over Beige

Maroon over Ivory

Forest Green over Beige

Black over Gray Blue over Gray

Leathers and soft top fabrics are selected to complement the exterior colors. Naturally, any other color combinations desired can be supplied on special order, subject to availability of suitable materials and design approval by Cumberford.

PERSONALIZATION

If you so desire, upon the door sill step plate can be engraved the legend:

Cumberford Martinique 000

is the personal motor car of

(your name or actual signature)

A reproduction of this plate can be mounted on a wooden plaque at your request, for display at home or in your office.

INVESTMENT VALUE

The question has been asked, "Is this car a good investment?" The answer must be "yes," if one is talking about an investment in driving pleasure, about an investment in a beautifully made object. But a car should be bought as a painting is bought: because it gives pleasure, not because it is speculatively a source of profit. However, it should be obvious that, just as a passionately-painted canvas by a living artist must have more value than a paint-by-numbers reproduction of a Great Master done on hardboard in acrylics, the Martinique has greater intrinsic worth than any car with a flashy body mounted on an ordinary sedan's chassis. Buy the Martinique to drive it, and drive it hard... it could be the best investment you've ever made!

CUMBERFORD MARTINIQUE

SPECIFICATIONS

BODY

Type:

Two seat convertible with disappearing cloth top, electrical window operation, central locking system, vertical seat adjustment for driver. Adjustable steering column.

Construction:

Cast aluminum exoskeletal structure integrated with chassis, wrought aluminum stressed floor and door structures, aluminum skin panels. Foam and aluminum crushable structures front and rear for crash energy attenuation. Aluminum bumpers, shock strut mounted. Fenders are made of wood/Kevlar/epoxy organic composite material, finished with polyurethane ultra-violet barrier clear coatings for weather protection. allcarindex

Weight:

2990 pounds.

ENGINE

Type:

BMW 3.2 liter inline 6-cylinder, 89mm bore, 86mm stroke, 3210 cc, 8:1 compression ratio, 174 bhp (SAE net) at 5200 rpm.

Maximum engine speed 6400 rpm Torque: 188 lb/ft @ 4200 rpm

Catalytic converter with Lambda probe, requires 91 octane (Research Method) unleaded fuel.

Construction:

Cast iron cylinder block and crankcase, fitted with an aluminum alloy cylinder head carrying valves at a 45° 30' angle in hemispherical combustion chambers. Single overhead camshaft driven by chain at the front. Forged crankshaft on seven main bearings. Bosch L-Jetronic fuel injection system.

TRANSMISSION

Gearbox:

ZF 3 HP-22 automatic transmission.

Torque converter multiplication ratio 2:1.

Ratios:              

I - 2.478:1

II - 1.478:1

III - 1:1

R - 2.09:1

Differential: Getrag 25% limited slip,

3.64:1 final drive ratio.

20.8 mph / 1000 rpm

CHASSIS

Structure:

Heat-treated A-356 cast aluminum integrated with cockpit section of body. All joints epoxy-bonded and pinned with high-tensile aircraft alloy steel fasteners. Welded steel crossmembers carry the engine and the differential. allcarindex

Suspension:

Equal-length forged alloy steel upper and lower arms at all four wheels. Inner pivots are roller bearings on the upper arm/ Fluidblocs on the lower. Anti-dive geometry for front wheels, anti-squat geometry for rear wheels. Constant ride height maintained by high-pressure hydraulic system. Anti-roll bars on both axles. Light alloy hub carrier uprights are integrated with brake calipers on all four wheels. Suspension is of the rising-rate type, with compressed nitrogen as the springing medium. Metal disc- type shock absorbers are integral with the pressure spheres.

Brakes:

Ventilated disc brakes at all four wheels, 10.25-inch diameter. Brakes are operated from central hydraulic system, with separate pressure accumulator and priority valve. Rear brakes use rear suspension spheres as pressure regulators, to proportion braking force to load on each wheel. Mechanical parking brake handle on central tunnel to operate rear wheels. allcarindex

Steering:

Powered rack-and-pinion with constant ratio, 2.5 turns lock to lock. Variable-rate power assistance diminishes in effect as speed rises.

Wheels:

Cumberford cast aluminum, 415mm diameter, 180 TR 415 rim section.

DIMENSIONS

Tires:

Michelin 240/55 VR 415 TRX radial tires, steel-and- Kevlar belted, Kevlar radial-cord sidewalls. Load rating 1710 pounds at 36 psi.

—                        Automatic Antenna

—                        Air Conditioning

—                        Cruise Control

—                        Check Control Monitor Panel

—                        Central Locking System

—                        Heated Seats

—                        Electric Windows

—                        Built-In Powered Jacking System

It is Cumberford Corporation's policy to make technical improvements at any time. These specifications are therefore subject to change without notice.

Text may not be reused without full credit to www.allcarindex.com and direct link to this webpage.