Classic cars, defined by the human hand

Prototype Parade No. 75 | Model Maker August 1956 | Drawn & described by R. Collett

AC Aceca

ALTHOUGH the majority of British cars are manufactured by mass production methods, there still remains a large number of smaller manufacturers who produce small numbers of hand-built cars which generally sell at a higher price than an equivalent quantity-produced car, but have that indefinable quality which distinguishes the car made wholly by craftsmen, from its lower-priced contemporaries. Such a car is the "ACECA," made by the A.C. Car Company of Thames Ditton.

When interest in sports cars was on the increase a few years ago, one of the many successful sports-racing specials was the TOJEIRO - BRISTOL. A.C. realised the potentialities of this type of car and decided to develop one of their own: they chose the Tojeiro chassis as a basis, fitted one of their own engines, added an attractive open two-seater body, and produced one of the best-looking sports cars on the British market. This was the "ACE," and it was first shown to the public at the London Motor Show of 1953. One year later they followed up this successful venture with a saloon version called the "ACECA." This saloon is intended as a fast, comfortable, touring version of the "ACE," and for this reason, although many of the components are identical for both cars, greater attention has been paid to silence on the "ACECA." In particular the final drive unit has been rubber mounted, and the bulk-head between the engine and passenger compartment is, of Fibreglass, which has excellent sound-damping properties. The body is of aluminium panelling on a framing of steel tubes and ash, and is up to the standard of the best Continental designs.

One of the outstanding features of the car is the 2-litre engine. This was originally designed in 1922, and throughout the 34 years of its life it has been gradually developed until it now gives 90 b.h.p. at 4,500 r.p.m. This engine makes extensive use of aluminium and is therefore extremely light, a factor which contributes considerably to the excellent power to weight ratio. The six cylinders have a bore and stroke of 65 mm. x 100 mm., and are fed by three S.U. carburetters. The valves are operated by a single chain driven overhead camshaft. The other feature of the car which merits attention is the suspension, which is independent on all four wheels. Transverse springs and wishbones controlled by telescopic dampers are used at both front and rear, and at their outer ends carry Girling hydraulic brakes which operate in 11-in. dia. Alfin drums mounted just inboard of the Dunlop wire wheels.

The single dry plate clutch and the four speed gearbox are built in unit with the engine and project into the passenger compartment between the occupants. Gears are changed by a short, centrally located cranked lever, and have ratios of top 3.96, third 5.43, second 7.85, first and reverse 13.5, with syncromesh on the upper three ratios. A Bishop cam steering box is fitted, and the steering wheel, which only requires two turns lock to lock, is adjustable for both rake and fore and aft position.

The main dimensions are :- Wheel base 7 ft. 6 in. Track, front and rtar, 4 ft. 2 in. Overall length 12 ft. 91 in. Overall width 5 ft. 1 in. Overall height 4 ft. 4 in. Ground clearance 6 in. Tyres, Michelin X, 5.50 x 16 in. As already mentioned, the "ACECA" has an excellent power to weight ratio, mainly due to the extensive use of aluminium in its construction. This, together with the all independent suspension, results in a car which has better acceleration and road holding than any of its rivals, and yet is capable of maintaining high average speeds over long distances, without fatigue to either car or passengers. During the past few months, both the "ACE" and the "ACECA" have been offered with the Bristol engine, which has greater power than the standard engine, and is usually fitted when it is intended to race the cars. Such a combination should provide a practically invincible contender in the 2-litre class.

Model Maker

AC Aceca

AC Aceca technical drawing
Car Model

AC Cobra

A.C. Cobra technical drawing

All Scale Plans | Car Model May 1964 | Plans by Jose Rodriguez Jr

AC Cobra

AT THE HEIGHT of his career as a driver, Carroll Shelby retired from the sport of road racing in 1961. He had been named "Driver of the Year" by Sports Illustrated in 1956. He was SCCA "Driver of the Year" in both 1956 and 1957, and in 1959 he teamed with Roy Salvadori to win that most coveted of all sports car victories, the 24 hours of LeMans. In 1960, Shelby was again named "Driver of the Year" this time by USAC.

Shelby's retirement from active competition didn't mean a retreat to a cozy den crammed with trophies. He had a dream —to produce the fastest production sports car in the world, and he set about making the dream become a reality right away.

The car Shelby built was called the Cobra but it was more than just another car, it was a part of Carroll Shelby.

Today the Cobra is known as the automobile that won three national championships in its first year of production and competition —truly an amazing record. In its very first year, the car earned the honor Shelby was seeking —fastest production sports car in the world. The Cobra is the result of mating a hancrafted AC body with a potent Ford 289 cubic inch engine. Let's go back and see how it was developed.

In 1960 and early 1961, Shelby discussed his dream with engineers and executives of General Motors, but didn't set the world on its ear with the progress he made. Then, late in 1961, he heard that the AC Auto Works, producers of the expensive AC Bristol sports car were about to go out of business.

He asked AC if they would agree to continue producing the body if he supplied American engines. At about the same time, he had heard of the development of the high performance Ford Fairlane mill. The combination of the two seemed a natural to Shelby. Both manufacturers agreed to co-operate, so Shelby went to England to supervise installation of the Ford power plant and to develop the resulting Anglo-American car.

They had to alter and beef up the chassis to handle the Dearborn mill, which was 2½ times the size of the "sewing-machine" Bristol engine that had powered the car before. The body was lengthened and many other modifications had to be made until, finally, the Cobra was an AC in appearance only. Shelby first installed a 260-inch Fairlane engine in the prototype (later switching to the more powerful 289 when it became available) and personally tested the car at the Myra and Goodwood courses, as well as in the streets of the town and in the country near the AC plant.

AC Cobra cutaway drawing

He brought the car to this country, where Ford engineers found it to be sound and recommended only a change to American electrical components, to assure that replacements would be readily available.

The Cobra entered its first race in October, 1962, a 3-hour enduro at Riverside. This also happened to be the race in which speed demon Mickey Thompson entered a team of two new Sting Rays. The battle shaped up as a direct confrontation of the two giants —Ford vs. Chevrolet.

Bill Krause, driving the Cobra, shot into the lead immediately and was steadily increasing his margin over the heavier, less maneuverable Sting Rays. After only a few laps, when he had already gone out in front by 30 seconds, Krause lost a wheel and had to withdraw, while Hooper, in one of the 'Rays, went on to win.

Early in '63, Shelby returned to the wars, but this time he was prepared —he had a team of two cars. At Riverside in January his drivers, Dave MacDonald and Ken Miles, finished one-two against one of the fastest fields of Sting Rays in SCCA ranks.

In those early months, the Cobra still had problems —overheating, steering, suspension— but the bugs were worked out, one by one, as Shelby concentrated on competition with the rival 'Vettes.

"It's just little ol' me against General Motors," he liked to say, as the Cobra gradually improved its position, in race after race.

Eleventh and seventeenth at Sebring; fifth at Pensacola's USRRC; one-two-four at Laguna Seca; seventh overall at LeMans . . . then came the string of victories that produced three big championships for Cobra and its drivers!

First at Lime Rock, Conn., in the national SCCA point race.

One-two-three at Watkins Glen, N.Y., U.S. Road Racing Circuit event.

One-two-three at Lake Garnett, Kans., national SCCA.

First at Thompson, Conn., national SCCA.

One-two-three at Kent, Wash., USRRC.

First at Meadowdale, Ill., national SCCA.

One-two-three at Castle Rock, Colo., USRRC.

First at Harewood, Ont., Canada, in an F.I.A. race. First at Watkins Glen, national SCCA.

One-two in the Elkhart Lake 500, a USRRC classic.

First at Bridgehampton, N.Y., in another F.I.A. race —also the first American car to ever win this event!

One-two in the USRRC finale at Mansfield, Ohio.

One-two-three-four in the F.I.A. race at Riverside, to climax the most amazing performance by an American built car in road racing history.

Yes, the Cobra simply gobbled up the opposition, winning the U.S. manufacturer's championship with 111 points. Just to give you an idea how badly Cobra poisoned the competition, second place went to Ferrari, way behind with only 28 points!

Bob Holbert, top Cobra driver, finished first in the National Championship point race, and Miles Shelby's competition manager and driver finished second. Bob Johnson broke a long string of Chevrolet championships to win the SCCA Class A production crown of the nation.

Meanwhile, the Cobra was proving as popular on the street as it was successful at the track. Production of more than 400 of the swift roadsters has failed to put a dent in the backlog of orders for the street version of the car.

The Cobra lists for $5995, and Shelby continues to maintain that he is interested only in limited production, so that the car can be sold only to "the true enthusiast."

The all-aluminum bodies are still hand formed in the British AC Carriage Works, and the car is detailed with leather upholstered bucket seats and wire wheels in the best sports car tradition.

There is a 4-speed, close ratio Sebring type transmission, and the fully independent brake system is of the Le Mans type, with 12-inch Girling discs. Final drive ratios are available from 4.56:1 to 2.72: 1 — top speeds of from 110 to 180 miles per hour, with stock equipment.

The Cobra is noted for its brutish, neck snapping torque and has been road tested with incredible results. Its acceleration is so good that several drag enthusiasts have entered the car in competitions of this type.

The car's original worm and sector steering, now available only for the drag racing models, has been replaced by rack and pinion. Instruments are Stewart Warner. In the late models, an air vent has been added to each side, directly behind the front wheels, to assist in engine cooling.

Shelby has also developed a racing coupe for long international manufacturer's races, based on the Cobra frame and engine, and is now experimenting with the huge 427 inch mill for prototypes of new models.

Last Fall, Shelby brought out another bomb, the Cooper Ford, and won three in a row —Riverside, Laguna Seca and Honolulu.

This year should see Shelby even more active and the Cobra marque even more potent, as he is expected to field teams of Cobras, prototype Cobras, Cobra coupes, Cooper Fords and at least two as yet unannounced new racing sports cars.

Competition, beware! Those Cobras are like poison fanged.

Model Car and Track

Alfa Romeo 8C 2900B

Alfa Romeo 8C 2900B technical drawing Alfa Romeo 8C 2900B technical drawing

Scale Plan Series #9 | Model Car & Track February 1965 | By Jonathan Thompson

Alfa Romeo 8C 2900B

T HE 8C 2900B Alfa Romeo, usually referred to as the "2.9," was certainly the most advanced and exciting sports car of the thirties. It might be considered the counterpart of today's Ferrari GTO with respect to performance and prestige.

A total of only thirty 2900B's appeared between 1937-39; two basic wheelbases were employed, the Corto (short) at 2799mm, and the Lungo (long) at 3000mm. The majority of the cars seem to have been two seat spyders, or roadsters, on the short chassis, although a number of more comfortable closed bodies were built on both lengths. The type featured here is the ultra light short chassis competition Mille Miglia roadster with bodywork by Carrozzeria Touring; two such cars took the first two places in the 1938 Mille Miglia driven by Clemente Biondetti and Carlo Pintacuda, while the American driver Phil Hill campaigned an identical machine in 1951, winning several west coast races, before beginning his well known association with Ferrari.

Both the 2900B and its immediate predecessor, the 2900A of 1935, utilized engines developed from the famous and extremely successful Monoposto Grand Prix cars of 1932-35. The original Monoposto (single-seat) Alfa Romeo had a 2.6-liter supercharged eight cylinder in-line engine in two blocks of four, with gear train for the camshafts and auxiliaries in between. In 1934 the displacement was upped to 2.9 liters and the car designated Monoposto Tipo B. The same engine was further enlarged to 3.2 and finally 3.8 liters for Grand Prix use, but the 2.9 size was still sufficient to power a successful sports car. The 1935 2900A sports car, of which only 11 were built during a two year period, was essentially a two seat Grand Prix car with such sports equipment as cycle fenders, spare tire, and lights. It closely resembled the 1935 8C 35 Grand Prix in appearance, while the all independent suspension was practically identical. The 2900A won the 1936 Mille Miglia, driven by Antonio Brivio, while second and third spots were filled by Pintacuda and Giuseppe Farina in similar cars.

The 2900B was mechanically related to the A version, but in bodywork and equipment it was a reasonably practical road machine, and the various models found many lucky buyers. In the opinion of the writer, the 8C 2900B Alfa Romeo represents one of the high points of classic high performance automotive design, although the engine, with its non detachable alloy cylinder head, was not ideal in terms of maintenance. There is no denying the power output, however; 180 b.h.p. was an excellent figure for a light sports model at that time. In 1938 the car was hailed in Italy as "la piu veloce vettura del mondo" (the fastest car in the world), although this claim was only valid with respect to road equipped cars available for sale, of course. In England a Touring bodied Mille Miglia roadster owned by Hugh Hunter was involved in a controversy as to what was the fastest road car in existence; although the results of several speed tests did not convincingly settle the dispute in favor of any one car, the Alfa was a front runner at all times. The 2.9 engine was a detuned version of the Grand Prix unit, the latter giving as much as 215 b.h.p. at 5400 r.p.m.

At least two Touring bodied Mille Miglia roadsters found their way to the United States, along with a number of other 2.9's of various body styles. The Phil Hill car was previously a part of the Tommy Lee collection. Hill won a minor trophy dash at Carrell Speedway early in 1951, while Arnold Stubbs took the same car to second place in the Sandberg Hill Climb. Phil won the Del Monte Handicap at Pebble Beach, and placed fourth in the Pebble Beach Cup. These were excellent performances for what was even then a 13-year-old car. This Alfa Romeo is now in the Brooks Stevens Automotive Museum in Milwaukee, Wisconsin.

SPECIFICATIONS: Engine, inline eight cylinder in two blocks of four; twin superchargers with two Weber carburetors; twin overhead camshafts and auxiliaries driven from the center of the engine; bore and stroke 68 x 100mm, displacement 2905cc; compression ratio 5.75/1; output 180 b.h.p. at 5000 r.p.m. Transmission, multi-plate clutch in housing at the rear of the crankcase, and four-speed non-synchronized gearbox in unit with the differential. Chassis, light gauge welded box section frame with all-independent suspension. Front suspension by trailing arms and coil springs, with telescopic shock absorbers in oil-filled cylinders. Rear sass. pension, swing axles located by radius arms and transverse leaf spring, with telescopic shock absorbers. Brakes, 17- inch hydraulic drum, front and rear. Tires, 5.50 x 19 Pirelli Coma front and rear. Fuel tank 38 gallons; oil tank 4.5 gallons.

DIMENSIONS: Wheelbase 110.2 inches. Track 53.1 inches front and rear. Length 176.4 inches. Front overhang 21.2 inches. Rear over-hang 45.0 inches. Height 42.2 inches (cowl), 48.0 inches (windscreen). Ground clearance 5.7 inches (sump). Tire diameter 30.7 inches, maximum section 6.4 inches. Wheel diameter (rim) 22.0 inches.

COLORS AND NUMBERING: Bodywork, dark red. Wheels, aluminum. Seats, brown leather. White numerals 143 on each front fender and on both sides of cowl (Biondetti, Mille Miglia 1938). The author wishes to express his ap-preciation for photographs, data, and blueprints supplied by Alpha Romeo, Milano. Detail drawings and photographs will be published in subsequent parts of this series to clarify construction of the model.

Model Cars

Alfa Romeo Type 33

Alfa Romeo Type 33 technical drawing

Prototype Parade No. 262 | Model Cars February 1968 | Described by Aldo Zana, drawings by Roberto Cereda

Alfa Romeo Type 33

A brand new, all Alfa, prototype was presented to the press on 6th March, 1967, in the testing ground of the factory, half way between Milan and Turin. The car, named "Type 33", was a rear engined one and with its 2,000 cc. engine was due to fight against the all conquering Porsches and the Dinos.

The body was very low, as streamlined as the short wheelbase allowed and the most outstanding feature was a large dynamical air intake over the rear bonnet in the 2D Chaparral style. The 33 looked like the new star in the two litres class for its claimed output of 240 b.h.p. and for its glorious name. The first race for the new car was a short hill climb near Fleron in Belgium where the test driver Zeccoli scored an easy win over a very poor field.

Two 33's were entered for the Sebring 12 hours race for the drive of De Adamich-Zeccoli and Bussinello-Audry; both the cars covered that flat and difficult track with astonishing speed, being faster than the new Porsches and the Dinos.

The start of the race was happy for the Alfa Romeo people with De Adamich in the lead and Bussinello third. Unfortunately, the 33's were out for mechanical troubles shortly after this performance.

The car proved itself very fast and powerful but was lacking in road holding, suffered from failures in the steering unit and was largely far away from reliability. The practice session for the Le Mans event confirmed the poor handling and the wrong streamlining of the Alfas, which lifted from the track at high speed on the Hundieres straight when raining, the water entering the air intake flooded the engine. A new longer and lower rear bonnet was tested but without a real improvement over the average speed.

Alfa Romeo Type 33 Stradale cutaway drawing

The Alfa team deserted the Monza race and entered four cars for the Targa Florio in Sicily; De Adamich-Rolland reached third place after the early withdrawal of the other three 33's but they were forced out, too. The car proved itself again powerful but still unreliable.

The work about the new Alfa continued and, at last, a 33 ended the Niirburgring 1,000 Km. race in the fifth place well below the winning Porsches, driven by De Adamich, Bussinello, "Nanni", Giunti. The four cars entered for the Mugello Circuit had a slightly different bodywork with larger front intake, but they were all out shortly after the half of the race. Le Mans and Brands didn't see the red prototypes on the starting grid, but the car was improving and it was raced in some minor hillclimb in Italy, but without victories. The 33 won its first circuit race at Vallelunga (Rome) on Oct. 15th over a small field of private entrants. The car was now reliable and easy to drive: at last the very long and hard testing work seemed to reach the end.

The frame of the car is a new design with a central monococque section where the fuel tanks are fitted and with two die cast magnesium arms for the front wheel suspension and steering unit and for the engine and the rear wheels. The cockpit is very crude and has plenty of room for the driver; the body is all fibreglass. The drive is of left hand type with right-handed gear lever (gear ratios: 6 +RM; this confirms the very narrow range of maximum power output); a small lever can close the air intake to avoid suction of water and dust, etc.

The wheels, die-cast from Alfa Romeo, are of oval section with a series of holes to assist disc brake cooling (the rear ones are near the differential unit); tyres are Dunlop Racing front and rear. The overall finish of the 33 is in the Italian racing red; the roll bar is black like the upholstery of the cockpit; the wheels are of natural metal and the exhaust pipes are ceramic white.

The Alfa Romeo badge is over the front of the body while the "Autodelta" triangle and the "quad-rifoglio" (four leaved shamrock) emblem are carried on both sides. The "quadrifoglio" is green over a white bottom, the word "Autodelta" is green, too. Front fenders and a tiny frame over the front air intake are optional.

Technical features and dimensions: Engine, V90° (4 o.h.c.) Number of the cylinders, 8 Bore and stroke, 78 x 52.5 mm. Capacity (cubic centimetres), 1,995 Steering, rack and pinion Front wheels, 8 x 13 mm. Front tyres, 5.25 x 13 mm. Front track, 4 ft. 4¼ in. Rear wheels, 9 x 13 mm. Rear tyres, 6.00/ 13.00 x 13 mm. Rear track, 4 ft. 9 in. Overall length, 11 ft. 9½ in. Overall width, 5 ft. 6½ in. Wheelbase 7 ft. 4½ in.

Alfa Romeo Disco Volante

Alfa Romeo Disco Volante cutaway drawing
Model Maker

Aston Martin DBR1 300

Aston Martin DBR1 300 technical drawing

Prototype Parade No. 89 | Model Maker November 1958| Drawings by Alan Dakers, described by the Editor

Aston Martin DBR1 300

IF sports/racing cars were classified on a concours d'elegance basis, there is little doubt that the Aston DBR1/300 would win acclaim on looks alone. When sparkling performance is added to handsome appearance, as in this case, it bears out the old maxim that you can always tell a thoroughbred on looks alone! An impressive list of competition wins enjoyed by this car and its related predecessors includes nearly every event in the calendar with the exception of Le Mans, where the marque has twice been second, five times class winners, but has failed as yet to collect the victor's laurels.

Aston Martin DBR1 300 artwork

Like many another thoroughbred, the DBR1 is no chance mutation, but the result of steady improvement and minor development over the years, so that, superficially at least, it is almost impossible to distinguish it from earlier models. It is not altogether surprising to find the name of Bentley in its family tree, on the engine sides since it stems from the original 21 litre designed for Lagonda by "W.O."

In its present form as a 3 litre class 6 cylinder car of 2,992 c.c. capacity it develops its maximum power of 265 b.h.p. at 6,500 r.p.m. The now almost universal Weber twin choke type carburettors are installed. Light alloy crankcase is a wet liner type. Pistons are Hepworth and Grandage. K.L.G.s furnish the 10 mm. plugs, and S.U. are responsible for the fuel pump. The latest crankshaft is a seven-bearing type, which has helped to make possible the increase in maximum revs from 6,000 to 6,500. Gearbox is mounted at the rear of the car, a change which brings the layout more into line with a growing G.P. practice.

This change, plus the weight of the laden fuel tank, at the rear does much to maintain the Aston's excellent reputation for roadholding and steering. Rear suspension is De Dion with Watt's linkage; trailing arm type using transverse torsion bars takes care of front springing. Girling pattern disc brakes are fitted.

Aston Martin DBR1 cutaway drawing

Wheels are Borrani wire-spoked pattern, shod with Avon racing covers - the only make of car so supplied. Tyre sizes are, front: 600/16; rear: 650/16. Three lug quickly detachable hub caps retain the wheels.

Other useful sizes are: Wheelbase : 7 ft. 6 in. Track, front: 4 ft. 3i in., rear: 4 ft. 32 in. Overall length: 13 ft. 22 in., width: 5 ft. 4 in. height: 3 ft. 21 in., scuttle height: 2 ft. si in. Ground clearance: 5 in.

We are very proud of the drawing of this car, for which we can take only limited credit, since it was supplied through the courtesy of Alan Dakers of David Brown's, and is the first "works drawing" ever supplied to us which it was possible to use almost exactly as sent. Indeed, the original had cross-sections at 10 in. stations, spacing so close that they would have been impossible to reproduce in plan form in the magazine. The very elegant lines of the original are carried out in magnesium alloy of approximately .03 in. thickness, which prompts us to suggest that a model version might well be beaten out in aluminium sheeting- a modelling tour de force which should be worthwhile in a project so pleasing to the eye.

Aston Martin DBR1 artwork on the cover of Model Maker magazine

Colouring is British Racing Green. The car illustrated on our cover, No. 8, is that driven by Carroll Shelby into third place in the four hour Tourist Trophy held at Goodwood this summer, when Moss (7) led from start to finish, with Salvadori (9) in second place, again driving similar cars. It differs slightly from the car in the drawing in that side lamps have been omitted, being covered with wire mesh grilles. Treatment of radiator bars and grille also seems to differ slightly on nearly every car inspected. Driver's cockpit is trimmed and upholstered in a kind of Bedford cord, not leather, in a shade of Vandyke brown.

Model Maker

Aston Martin DBR4 250

Aston Martin DBR4 250 GP technical drawing

Prototype Parade No. 97 | Model Maker October 1959 | Drawings by J.H. Batchelor, described by D.J. Laidlaw-Dickinson

Aston Martin DBR4 250

MOST interesting event of 1959 to our mind has undoubtedly been the entry of the David Brown organisation into Formula 1 racing. In a season when Moss has lacked a tried machine and flitted from car to car in an unavailing search for speed and reliability, we are surprised, indeed flabbergasted, that he has not teamed up with the new DBR4/250, particularly as he is reported to have lapped it on test at within one-hundredth of a second of Goodwood's then lap record.

The regular team drivers Roy Salvadori and Carroll Shelby have made a good first season's showing in a limited number of entries, but would be the first to admit that the genius of Stirling might have produced winning brackets.

The car follows closely on Aston Martin tradition in looking like a racing car. It is large as G.P. cars go, to be classed with Vanwall in point of size and in no way panders to the current scaling down that has resulted from the successes of the tiny Cooper. Its severely classic lines combine some of the more pleasing features of both Vanwall and Ferrari, presented as only Aston Martin could. A high tail incorporates the driver's headrest. Bonnet is well extended in a graceful streamline shape, with complete absence of curious excrescences to mar its lines. Twin exhaust pipes go straight back at just below cockpit level and are then angled up in a double bend to be almost clear of the rear wheel. On the other side a massive air intake is streamlined into the body lines. This is indeed the one bump on an otherwise pure frontal shape and may, we are told, later be redesigned to reduce frontal area. Screen is the typical wrapround style that has almost ousted the old "aero screen" type of racing windshield.

Six cylinder engine has a capacity of 2,493 c.c. Two plugs per cylinder are fitted. Weber supply the three double-choke carburet-tors. Provision is made for use of a portable electric starter through the frontal bonnet opening.

Engine and drive shaft is sharply offset going almost diagonally across the frame, with driver's foot controls on its right. A corner of the seat is cut away to give room for the five-speed gearbox on the right. Instrument panel is stark and practical with the five essential dials only and ignition switches grouped neatly to avoid possible confusion.

Chassis owes much to the many years of racing development with the company's sports/ racing cars which eventually achieved their first win at Le Mans this year. It is a space frame using small diameter tubes. Front suspension is wishbone, with coil springs enclosing telescopic dampers. Steering is rack and pinion. De Dion is featured at the rear with Watts linkage. All four brakes are outboard disc type by Girling. As usual, Avon supply the racing covers, 6.00 x 16 front and 7.00 x 15 rear, which are fitted to Bor-rani wire wheels.

Aston Martin DBR4 250 artwork on the cover of Model Maker magazine

Colour scheme is traditional B.R.G., but not so bright as artistic licence has depicted, on our cover! Racing numbers are in black on white discs. Steering wheel is usual three spoke alloy type with wooden ring attached to alloy core to avoid hand slip when hot (that is usually!)

Making their debut at Silverstone on May 2nd, the marque scored a second place in the hands of Salvadori: the other car driven by Shelby unfortunately retiring on the 48th lap. At Zandvoort at the end of May, the two cars failed to finish. In the British Grand Prix Salvadori shared front line on the grid and fastest practice time with Jack Brabham and finished 6th. Shelby retired near the end with ignition trouble after going well. Salvadori again finished 6th in the Portuguese G.P., when Shelby finished. In their first season, therefore, the cars have produced at least one finisher out of two in three out of four outings, which is a record few new cars can claim if we consider the history of now famous cars in their try-out period.

Model Maker

Austin Healey 100

Austin Healey 100 technical drawing

Prototype Parade No. 59 | Model Maker September 1954 | Drawings by Austin Motor Company

Austin Healey 100

IN pre-war days motorists were offered a variety of fast sports cars some of which were reputed to achieve the coveted "ton" of 100 m.p.h. However, except in the very highest price brackets, this figure was touched, not held, and the proud possessor of such a car was wont to boast of the merest flicker of a speedo. needle around that three-figure mark. Not so with the Austin-Healey 100 which provides in standard form a vehicle with a road-tested speed of 111 m.p.h., and a top speed as a stripped production car of 142.636 m.p.h., fastest mile ever recorded for a car of this class under 3,000 c.c. capacity.

Moreover it has been tested on the Bonneville Salt Flats (September, 1953) to average 104.3 m.p.h. over 24 hours continuous running, and 103.9 m.p.h. over 30 hours running. These figures established it at once as something out of the ordinary: that other manufacturers have been swift to produce fast machinery in the same category is sound evidence of the demand developed by the Austin-Healey.

It says much for the enterprise of the two companies concerned that they got together to produce a joint effort that so happily marries the sports and trials experience of Donald Healey with the reliability and production potential of the vast Austin organisation. The result is an attractive machine of elegant low lines, powered with the thoroughly tested Austin A90 o.h.v. engine. This four cylinder engine has a bore of 87.3 mm., stroke of 111.1 mm., with a total cc. of 2,660. B.h.p. is 90 at 4,000 r.p.m., compression ratio 71 to 1. A central gear lever controls three forward speeds and reverse, with syncromesh for all gears. An overdrive unit is fitted behind the gearbox, and engaged by a control switch mounted on the dash. This may be engaged in second and top gears, providing in effect a choice of five gear ratios. Gear ratios are 9.28, 5.85 and 4.125: with overdrive engaged 4.42 and 3.12 using the 4.125 axle.

Austin Healey 100 side views

Suspension is by independent coil springs controlled by double acting shock absorbers, interconnected by an anti-roll torsion bar for the front, while the rear is taken care of by semi elliptical springs, with double acting hydraulic shock absorbers and anti-sway bar. Brakes are Girling hydraulic with two leading shoes in front. Wheels are wire spoke knock on type with 5.90 by 15 in. tyres, or alternatively 6.00 x 15 in. Two 6v. 50 amp.-hour batteries provide the electricity, while there are built in head, side and twin tail lamps. Instrument panel includes fuel gauge, oil and water temperature gauges, 120 m.p.h. speedometer, and 0-6,000 rev. counter. Those desirous of racing the car will find the manufacturers most cooperative, with a variety of modifications, which enable power to be stepped up from 90 b.h.p. at 4,000 r.p.m. to 110 b.h.p. at 4,500 r.p.m. This can, it is claimed, be achieved with their Le Mans Engine Kit, without removing engine.

Austin Healey cutaway drawing

In spite of its amazing performance the Austin-Healey is a fully equipped and docile open two seater which can provide all the comforts so necessary to the inclement British climate. Individual bucket seats are provided, there is a large enclosed rear luggage compartment, full weather protection, with disappearing hood, detachable moulded perspex side screens and folding windscreen. The clean lines of the Austin-Healey make it an attractive project for the model maker, who might find it an opportunity to try out the new model techniques in glass fibre construction. Main dimensions are as follows, or may be taken off the drawing: length overall 12ft. 7 in., width overall 5 ft. 0½ in., height overall 4 ft. 1¼ in.; track, front 4ft. 1 in., rear 4ft. 2¾ in., ground clearance 5½ in.

Model Maker

Auto Union Type C

Auto Union Type C technical drawing

Prototype Parade No. 98 | Model Maker December 1959 | Drawn & described by Walkden Fisher

Auto Union Type C

CONSIDERABLE astonishment was caused in the racing world of 1934 by the appearance of the sensational and unorthodox rear-engined German P-wagen. This was something quite new - 'a new name, a new contender for Grand Prix laurels. It was variously described as resembling a fish, a torpedo and a cigar. Sponsored by 'a private group of wealthy German sportsmen, the late Dr. Ferdinand Porsche was responsible for the design, and the producers were the recently formed Auto Union group, consisting of the DKW, Wanderer, Audi and Horch concerns.

Auto Union Type C side view

In July, 1934, the title P-wagen was discarded and the designation Auto Union came into general use, a name that was to become increasingly familiar on the world's racing circuits, as together with Mercedes-Benz, these silver projectiles completely dominated Grand Prix racing until the outbreak of World War II. This period is generally regarded as being the most exciting in the whole history of motor racing, during which immensely powerful cars battled for supremacy.

A number of versions of the Auto Unions appeared during the years 1934-39, culminating with the 12-cylinder Type "D" featured in MODEL MAKER, Plan No. 134. All were rear-engined machines following Dr. Porsche's theories on this arrangement. The "C" Type is probably the most noteworthy and during the 1934-37 750 k.g. formula the cars competed with great success.

The design of the Auto Union was notable for simplicity and straight-forward engineering with no effort to solve problems by resort to complicated expedient. This principle extended to the very potent 16-cylinder power. unit which was also of basically simple construction.

During these four years the engine capacity of the 16-cylinder unit was raised in two stages from 4.36 litres to 6 litres, and engine output from 295 b.h.p. at 4,500 r.p.m. to 520 b.h.p. at 5,000 r.p.m. A Roots supercharger was incorporated in the cars. This was driven by spur wheels from the vertical camshaft drive and a five-speed gearbox was mounted behind the rear-axle centre.

On the early versions a tubular frame was used to carry water to the engine from the front-mounted radiator, and all four wheels were independently sprung, using Porsche-type trailing links and torsion bars on the front and a swing axle with transverse leaf spring at the rear. In 1936 separate water pipes were used as it had been found that the welds in the tubular frame used in the 1934 design were not 100 per cent watertight.

The placing of the forty-six gallon fuel tank and the engine behind the driver brought the latter very far forward in relation to the wheel-base, and it was possible to mount the driver very low on the car with no complication arising in respect of propeller shafts and clutch housings, etc. Weight distribution was unaffected by changes in fuel level, and fitted with the highest possible gearing, these powerful monsters could considerably exceed 200 m.p.h. With lower gearing, used for road races, they would reach over 180 m.p.h. The Auto Union was, however, a difficult car to drive. Owing to the extreme forward mounting of the driver the tail could move through a considerable angle before the pilot realised the breakaway point had been reached, and it was not easy to gauge the precise position of the rear end. Although such notable drivers as Nuvolari, Varzi, and Stuck performed creditably with these machines, only Bernd Rosemeyer really mastered them and was able to make use of anything like their maximum performance.

British racing enthusiasts were able to see these fabulous cars in action on two occasions in this country when, together with the Mercedes Benz team, they came over to compete in the Donington Grand Prix races of 1937 and 1938. The Auto Union teams proved victorious in both events, and with the high, snarling scream of their engines, coupled with their staggering speed, they provided a spectacle which never before or since has been experienced on a British racing circuit!

Auto Union Type C cutaway drawing

Mystery shrouds the ultimate fate of the Auto Unions because apparently not a single car has come to light since the end of World War II. Although it was rumoured in 1957 that one of the V-16s had at last been discovered, nothing further was reported. The late Dr. Ferdinand Porsche, with his brilliant, revolutionary designs can truly be regarded as one of the world's greatest automobile engineers and the influence of the Auto Union rear-engined construction is still apparent in many post-war racing cars. Today, his theories continue to be developed by his son, Dr. Ferry Porsche, who heads the experimental works and car firm bearing his name at Stuttgart.

As a subject for small scale modelling the Auto Union holds considerable interest. Readers are reminded, however, that minor differences could be seen in cars of the same mark. An example of this is the fact that some versions of the "C" Type had streamlined fairings fitted over the front and rear suspensions, while others appeared with these units entirely unenclosed as shown in the plan.

The writer has constructed 1/32 scale models of the "C" and "D" Types for electric rail racing and from personal experience has found both to possess exceptional road-holding qualities even on the sharpest of corners. This is attributed mainly to the long wheelbase, which certainly appears to influence their performance favourably.

Wheelbase: 9 ft. 6½ in. Track front: 4 ft. 8 in. Track rear: 4 ft. 8 in. Maximum width of body: 38 in. Tyres: Continental. Front, 5.25 x 17. Rear, 7 x 19 or 7 x 22 optional. (Note the large sizes for the rear wheels). Other interesting details - Engine : 16 cylinder. 6,006 c.c. 520 h.p. Valves : 32 Two per cylinder. Car-buretter: 2 Solex. Super-charger: Roots driven at engine speed x 2.11. Frame: Tubular. Front suspension: Porsche type trailing links with torsion bars. Rear sus-pension: Swing axle with torsion bars. Wheels: Rudge detachable. Shock absorber type: Friction. Brake system: Lockheed two leading shoe with double master cylinders.

Model Car and Track

Auto Union Type D

1938 Typ D (Nuvolari, Monza)

Auto Union Type D technical drawing

1938 Typ D Stromlinien Wagen (Reims)

Auto Union Type D technical drawing

1938 Typ D (Muller, Nürburgring)

Auto Union Type D technical drawing

1939 Typ D (Nuvolari, Nürburgring)

Auto Union Type D technical drawing

Scale Plan No. 4 | Model Car & Track July 1964 | Drawn & described by Jonathan Thompson

Auto Union Type D

The Auto Union group was formed in 1933 from the German manufacturers Audi, DKW, Horch, and Wanderer, with headquarters at Zwickau. The 1934-37 Auto Grand Prix car, originally known as the P. Wagen after its creator Dr. Ferdinand Porsche, was an extremely successful design. It underwent little significant change during its career in spite of a very unorthodox layout.

The only major change was a steady increase in the displacement and power output of its rear-mounted V16 engine, as follows: 1934 Typ A — 4360 cc/295 b.h.p.; 1935 Typ B — 4950 cc/375 b.h.p.; 1936-37 Typ C — 6006 cc/520 b.h.p.

During 1934-35 the Auto Unions were close competitors of the Mercedes-Benz W.25/25B; in 1936 the Typ C driven by Bernd Rosemeyer almost completely dominated the Grand Prix scene, much to the disgust of the Mercedes technicians, who were having nothing but trouble with their car, the handling being particularly bad. In 1936 Auto Union won the Tripoli, German, Swiss, and Italian grands Prix, as well as the Eifelrennen and the Coppa Acerbo. The Zwickau firm had bested Mercedes in five of eight encounters, although Tazio Nuvolari defeated Auto Union on four occasions with his Alfa Romeo! In 1937 the completely redesigned Mercedes-Benz W.125 regained the advantage for Stuttgart, but it must be pointed out that Auto Union had considerably less in terms of financial resources and capacity for research.

The Porsche machines were as a result less highly stressed; the design was expected to serve longer than the Mercedes (revised yearly), and in the case of individual cars to run in more races without major attention (the Mercedes cars were usually thoroughly rebuilt after two or three events). Thus the accomplishments of Auto Union are all the more praiseworthy.

Much credit must of course be given to Bernd Rosemeyer (one of the three truly great prewar Grand Prix drivers along with Tazio Nuvolari and Rudolf Caracciola), whose driving was really incredible. It has often been stated that only Rosemeyer, and later Nuvolari, could handle the reputedly vicious and undisputedly oversteering Auto Unions, but in fact the cars were also very well driven by Hans Stuck, Achille Varzi, and Hermann Muller. Rosemeyer was simply the only consistently first class driver Auto Union possessed, while Mercedes-Benz had the services of Caracciola, Manfred von Brauchitsch, Richard Seaman, and Hermann Lang, any one of whom might well have taken the Auto Union in stride had he found himself in the rival team. It might also be mentioned that it is relatively difficult to assess form during this period, when many accidents, retirements, and low placings were the result of burst tires, almost unknown in racing today.

For the new 3-liter formula commencing in 1938 Auto Union had a new car in the works, but the death of Rosemeyer in February of that year during a record breaking attempt caused the firm to give serious thought to retirement from racing. Muller, Rudi Hasse, and Christian Kautz had been signed, however, and the development of the new car was continued. Dr. Porsche had left the company, the design being that of Director Werner, Ing. Feureisen, and Prof. Dr. Ing. Eberan von Eberhorst.

Although another V16 was rumored, the engine turned out to be a single stage supercharged 3-liter V12 with three camshafts, one between the cylinder blocks operating the intake valves and two operating the exhaust valves. Output was initially 420 b.h.p. at 7000 r.p.m. (compared with 520 b.h.p. at 5000 r.p.m. for the 6-liter V16). The chassis retained the Auto Union features, although the wheelbase was reduced from 114.5 inches to 108.2 inches, the steering geometry improved, and a de Dion rear end employed. The 5-speed gearbox and Z.F. limited slip differential were essentially the same, front suspension was again by transverse torsion bars and trailing arms, and the central fuel tank position was kept. On the 1938 car, however, this consisted of two side tanks connected by a central filler behind the driver (total capacity 60 Imp. gallons). This change plus the shorter engine allowed the driver's seat to be moved back substantially on the frame. The new driving position (along with the steering and suspension modifications, which changed the car from oversteering to inherent understeering characteristics) contributed to a great improvement in handling.

Despite the reduction in wheelbase, track, and engine displacement, the all-up weight of the car (2816 lb.) was actually greater by approximately 300 lb. than the older "big" car. Frontal area with the early 1938 body was also up from 10.8 to 11.5 sq. ft., and specific fuel consumption increased from about 4 m.p.g. to about 3 m.p.g. (which accounted for the large fuel capacity, 33 per cent greater than that of the 6-liter's 46 Imp. gallons). All of these changes, coupled with the reorganization of the design staff and the delay following the death of Rose-Meyer, set the appearance of the new car back several months. The car was tested at Monza in March, but due to various troubles it missed the Tripoli race and was not even ready for the Eifelrennen (subsequently cancelled as a result). At Monza the car had appeared with 16 exhausts stubs protruding from the engine compartment, disguising the nature of the new engine!

The first official appearance of the cars was at Rheims in July. Two special streamlined cars (Stromlinienwagen) were driven in practice by Muller and Hasse, both of whom unfortunately crashed, the former putting himself in the hospital. The streamliners were similar in form to the record-breaking machines of 1936-37 but had the new Grand Prix chassis. The drag coefficient was a low 0.20, compared to about 0.60 for the standard body. Speeds were competitive with those of the W.154 Mercedes, but instability was so great that after the crashes the development of the aerodynamic cars was abandoned altogether.

Auto Union did not intend to start in the race (July 3), but Mercedes-Benz, which would have been deprived of any reasonable competition, prevailed upon them to run anyway. Hasse and Kautz came to the line in standard cars, which had an interim bodywork similar in form to that of the Typ C except for the side tank fairings. Kautz spun, stalled, and retired on the first corner, while Hasse got little further, hitting a bank and breaking the axle. Neither car recorded a lap! Manfred von Brauchitsch won for Mercedes at 101.30 m.p.h.

After Rheims Auto Union enlisted the two veterans Louis Chiron and Hans Stuck to test the cars at the Nurburgring, the latter recording a respectable but not startling 10 min. 35 sec. On July 8 Nuvolari, who had left Alfa Corse after a frightening fire incident at Pau in an 8-cylinder Alfa Romeo 308, arrived at the Eifel mountain circuit to begin some fast practice in the German car, eventually clocking 10 min. 3 sec. (Brauchitsch had recorded 9 min. 49 sec. in a Mercedes).

Nuvolari signed with the team, beginning with the German Grand Prix on July 24. Driving a new car with revised 37 bodywork, he followed Lang closely at the start, but was soon passed by Caracciola and ended up off the road after a momentary slip on the second lap. Stuck finished third in the other new Auto Union, while Nuvolari took over Muller's earlier model to finish fourth. Hasse, driving another "old" model, retired with engine failure. The race was a triumph for Dick Seaman in a Mercedes at 80.75 m.p.h. after a fire in the pits ruined Brauchitsch's chances for almost certain victory.

The new Auto Union bodywork was considerably more rounded and graceful than that of the cars which had run at Rheims. Although the frontal area was increased slightly to 11.8 sq. ft. the drag coefficient was markedly reduced, particularly by the lower cowl and extended tail. Radiator air was ducted out the sides of the car behind the front wheels.

Still not satisfied with the cars, Auto Union passed up the Coppa Ciano (at Nuvolari's favorite circuit, Livorno) and appeared next at Pescara for the Coppa Acerbo, August 14. Four cars were entered for Nuvolari, Muller, Hasse, and Kautz, the last two driving the earlier models. Nuvolari encouragingly set the fastest lap in practice, but all four Auto Unions retired from the race, as did Lang and Brauchitsch in their Mercedes. Rudi Caracciola finished first in the sole remaining German car at an average speed of 83.69 m.p.h., followed by Giuseppe Farina in an Alfa Romeo.

The following week (August 21) saw the team at Bern for the Swiss Grand Prix. Nuvolari did some fairly fast times in practice but was not particularly happy with the car, while both Muller and Stuck went very fast. The race occurred in pouring rain. Stuck made a good start but the Auto Unions were not really competitive, being further hampered by plugs oiling up. Muller ran well in third place until near the end when he struck a tree and tore the rear end off his car. Stuck finished fourth, Nuvolari ninth (!), while Kautz retired the fourth machine after plug and carburetor troubles. Once again victory went to Caracciola (a master in the rain) at 89.44 m.p.h.

Auto Union finally scored in the Italian Grand Prix at Monza on September 11. Tazio Nuvolari delighted the Italian crowd with his superb driving and a convincing victory at an average speed of 96.70 m.p.h. The cars of Muller, Stuck, and Kautz retired, but so did the Mercedes of Brauchitsch, Seaman, and Lang. Caracciola ,had one of his very rare off course excursions, but the car finished third driven by Brauchitsch. The Italians were further pleased by the second place Alfa Romeo V16 of Farina. Lang led Nuvolari for eight laps but once the little Italian got by he took complete charge of the race. Except for a brief drop to second after a pit stop for tires and fuel, he led to the finish.

The Donington Grand Prix was originally to have been held the first week in October, but the Munich crisis caused it to be delayed until the 22nd. Nuvolari was again in great form, recording 2 min. 11.2 sec. in practice after hitting a stag! Only Lang beat this time (by 0.2 sec.). In the race Nuvolari took an immediate lead, followed by Muller, four Mercedes, and Hasse and Kautz in the other two Auto Unions. Kautz retired early after two spins. Nuvolari soon had an advantage of 21 sec., while Muller continued to hold off Seaman's Mercedes-Benz. Muller gained the lead when Nuvolari stopped for a plug change, dropping to fourth. Hasse's Auto Union left the road backwards after spinning on some oil, followed shortly after by Seaman. This advanced Nuvolari to third, behind Lang.

The German driver had his turn in front when Muller came in to refuel, and Nuvolari, driving ever faster, passed his teammate to lie second, 21 sec. behind Lang. On the 43rd lap Nuvolari broke the record in 2 min. 14.4 sec. and was now only 12 sec. behind the Mercedes. This he made up in four laps to take the lead and his second consecutive victory for Auto Union. Muller finished fourth. Auto Union could be proud of this conclusion to the 1938 season; although two cars had retired, it was through driver error in the case of Kautz and just plain misfortune with Hasse. Nuvolari's wining average was 80.49 m.p.h.

The team went to Monza again in March 1939 for early season training. The 1939 Auto Union differed little from the previous year, although a portion of the radiator air flow was ducted out louvers in the top of the hood, while the intake was smaller and the side exits partly shrouded to improve aerodynamics.

The first race of the season for Auto Union was the Eifelrennen, held at the Nurburgring on May 21. In practice Nuvolari tied for second fastest with Caracciola at 9 min. 57 sec., Lang being the quickest at 9 min. 54 sec. Lang went even faster in the race, and took first place at an average speed of 84.15 m.p.h., while Nuvolari came in second after a non stop drive. The Continental tire technicians had advised him not to try to go the whole distance on one set of tires, but at the end he still had enough rubber for another lap. All the Auto Unions finished, although the remainder were in relatively low positions, Hasse being fifth, Bigalke (a new team member) sixth, and Muller seventh. The Eifelrennen was only ten laps (a "sprint" race) compared to 22 laps for the German Grand Prix on the same circuit.

The tragic Belgian Grand Prix, run at Spa on June 25, saw the death of Dick Seaman, who crashed in the rain while leading. The Auto Unions were never a strong challenge, although Nuvolari was as high as third before going off the road. Georg Meier, another new Auto Union pilot, had also crashed, and Muller retired as well. Rudi Hasse did well to finish second, one lap behind Lang, who won at an average of 94.39 m.p.h. and net the fastest lap at 101.35 m.p.h. On the same day Hans Stuck achieved hollow victory for Auto Union at Bucharest, Rumania, there being no significant opposition.

The French Grand Prix was held at Rheims on July 9. It could not have been more different from the race of the previous year, Auto Union and Mercedes fortunes being completely reversed. The 39 circuit had been improved and speeds increased considerably; Lang did 117.5 m.p.h. in practice and Nuvolari was also in the front row with 116 m.p.h. Both Nuvolari and Muller had new two stage supercharged cars, distinguished by external air intakes on the right side of the engine compartment leading to a bulge at the back. Power output was 485 b.h.p., although over 500 b.h.p. was recorded briefly.

Nuvolari led off with a standing first lap average of 115 m.p.h., while Lang was right behind him. Caracciola had already crashed on the first lap! Nuvolari stayed ahead for eight blistering laps before his Auto Union blew up. Lang took over the lead but both he and Brauchsitch eventually retired, leaving Auto Union a one-two victory. Muller was first at 105.25 m.p.h., followed by Meier a lap behind. Although Lang had set the fastest lap, no Mercedes finished.

Caracciola and Mercedes-Benz got their revenge at the Nurburgring on July 23. He averaged 75.18 m.p.h. in scoring his sixth German Grand Prix victory and also set the fastest lap at 81.66 m.p.h. Muller finished second with a two stage Auto Union, while Nuvolari and Stuck retired in similar machines. Hasse and Meier, in older single stage cars, also failed to complete the course.

The Swiss Grand Prix (August 20) was run in two heats and a final, the first heat for voiturettes (1500 cc), the second for the big cars, and the final for both. Lang won the second heat and the final, although the first heat winner, Farina's Alfa Romeo 158, turned in an amazing performance. Farina held second for six laps and eventually finished sixth. Two Auto Unions came in fourth and fifth (Muller and Nuvolari, respectively); Hasse and Stuck retired. Lang's winning average was 96.02 m.p.h., although Caracciola put in the fastest lap at 104.32 m.p.h.

The last race of the dramatic prewar period, and the final race for Auto Union, was the Belgrade Grand Prix held in Yugoslavia on September 3, coinciding with the outbreak of the Second World War. Two Auto Unions (Nuvolari and Muller) faced three Mercedes (Lang, Brauchitsch, and Baumer). Although Lang and Brauchitsch led in turn, the former blew up and the latter spun, letting Nuvolari into the lead which he held to the end. Muller finished third.

The Auto Union Typ D was slow to be developed in 1938 and was outpaced in 1939 by the Mercedes-Benz W.163, but it won four major races and one minor event, scored four second places and two thirds. The Auto Union V12 produced slightly more power than its rival (485 b.h.p. compared with 483 b.h.p. for the W.163); in addition, both weight and frontal area were less. Both cars, properly geared, could achieve 195 m.p.h. Nevertheless, the cars from Stuttgart were nearly always faster around the circuits than the Auto Unions, except when Nuvolari was really going fast!

Had Auto Union possessed second and third string drivers of the caliber of Lang and Brauchitsch, plus a more efficient organization, the races of 1938-39 would have been even more closely fought. At any rate, the Porsche designed rear engined machines set the style for the Grand Prix cars we know today, although it took the rest of the racing car manufacturers more than tvventy-five years to catch on!

SPECIFICATIONS: Engine, 90-degree V12; three gear-driven overhead camshafts (one intake, two exhaust); single-stage (later two-stage) Roots supercharger driven from rear end of crankshaft; 65 x 75mm., 2990 cc; 420 b.h.p. (later 485 b.h.p.) at 7000 r.p.m., 140.4 (162.2) b.h.p.1 liter; compression ratio 10/1. Three-plate clutch in oil. Transmission, 5-speed all-indirect gearbox in unit with Z.F. limited-slip differential. Tubular steel frame. Front-mounted radiator and oil cooler. Front suspension, Porsche parallel-action trailing arms with transverse torsion bars and double-acting hydraulic shock absorbers. Rear suspension, de Dion with Panhard rod for lateral location, longitudinal torsion bars and double-acting friction shock absorbers. Fuel capacity, 60 Imp. (71 U.S.) gallons. Brakes, 4-leading shoe hydraulic drum type, 15.75-inch diameter. Rudge detachable wire wheels. Tires, Continental 5.25 x 19 front, 7.00 x 19 rear, or for fast circuits, 5.50 x 19 front, 7.00 x 22 rear.

DIMENSIONS: Wheelbase 108.2 inches. Track 55.1 inches, front and rear. Ground clearance 3 inches. Weights, 1938 lb. dry, 2816 lb. with fuel (568 lb.), oil (70 lb.), water (65 lb.), and driver (175 lb.).

BODY DIMENSIONS, Reims streamliner: Length 201.0 inches. Width 74.9 inches. Height (cowl) 36.8 inches. Height (headrest) 44.0 inches. Frontal area 15.7 sq. ft. Early. 1938 car: Length 158.5 inches. Width 45.0 inches. Height (cowl) 36.8 inches. Height (headrest) 41.8 inches. Frontal area 11.5 sq. ft. 1938-39 car: Length 164.5 inches. Width 47.5 inches. Height (cowl) 35.5 inches. Height (headrest) 44.3 inches. Frontal area 11.8 sq. ft.

COLORS: Bodywork, silver (polished aluminum). Seat, beige. Numbers, red. Auto Union device, black.

CAR NUMBERS: Reims 1938: Hasse 16, Kautz 20 Nurburgring 1938: Nuvolari 2, Stuck 4, Hasse (old type) 6. Muller (old type) 8. Pescara 1938: Muller 30, Nuvolari 40, Hasse (old type) 44 Bern 1938: Nuvolari 6, Stuck 8 Monza 1938: Muller 20, Nuvolari 22 (red nose band) Donington 1938: Muller 1, Hasse 2, Kautz 3, Nuvolari 4 Nurburgring (Eifelrennen) 1939: Nuvolari 2, Muller 6 Reims 1939: Muller 14,Nuvolari 8 Nurburgring (G.P.) 1939: Nuvolari 2, Stuck 4, Muller 6, Hasse 8, Meier 10 Bern 1939: Nuvolari 2, Muller 6