Aston Martin DB Mk III


Road Tested in 1954

The Aston Martin Mark III special series tested by Roy Salvadori

The profile of the Mark /II remains unaltered with the classic long bonnet of the British sports car

THE Mark III version of the well-tried Aston Martin offered a number of improvements over the previous DB2-4 model and now, for the first time, to cater for the enthusiasts who require additional performance, a special series version of the Mark III is available. The car is basically similar in specification to the standard model, except that three I!-inch S.U. carburetters are employed, together with a dual exhaust system which boosts brake horsepower from 162 to 195 on an 8.6 to 1 compression ratio but at the same r.p.m. of 5,500. The very considerable increase in power gives the opportunity of some memorable motoring to those who like going far, fast and safely. This I will go into fully in a few moments but to set the record straight it is interesting to recall some of the improvements which can now be found on the Mark III model.
Detail styling improvements have been effected on the exterior of the car-notably at the front end, where the rather angular (although well-loved by Asto-philes) grille has been replaced by a smoother, more contemporary version. The door-handles are also sleeker and rear light arrangements have been modified. Under the bonnet, the engine remains basically the same. For the standard Mark III, on an 8.2 to 1 compression ratio 160 net b.h.p. is developed as against the 140 of the DB2-4 at 5,000 r.p.m. The special series version that I tested, of course, has three carburetters and the augmented power output mentioned above. The steering is now by Maries worm and roller against the previous cam and double roller type. Suspension is still by coil springs to all four wheels-at the front with trailing links and anti-roll bar and at the rear with parallel trailing links and Panhard rod. The front wheels of the car are now fitted with Girling disc brakes of 12-inch diameter and with a hydro booster incorporated in the hydraulic system. The use of this Baldwin booster certainly improves the amount of pedal-pressure required for hard stopping and at the same time a very good degree of sensitivity is maintained. Personally, however, I have a certain dislike for such systems purely because the hard, positive feel of direct braking is absent and pedal travel is inclined to increase almost imperceptibly. This booster unit gives two-stage assistance on pedal pressure by the use of two pressure chambers containing a compound piston. With the first gentle application of the brake, a low-pressure cylinder operates and brings the pads, in the case of the front

January, 1959

wheels, and linings in the case of the rear wheels, into contact with the discs and drums. As pressure is increased on the pedal the second stage comes into operation, reducing the pedal effort required by approximately 30 per cent. The simplicity of the system has much to commend it and there are no extra complications regarding the bleeding of the brakes. The chassis frame remains of rectangular steel tubing, with large cruciform bracing, ensuring extreme rigidity. The interior of the car has undergone a noticeable face-lift, particularly on the facia and seating. The traditional-type of English dashboard has now been abandoned in favour of instruments grouped in front of the driver. In the case of this Aston it has been done in a particularly pleasant manner, allowing excellent viewing of the revolution counter and speedometer through the upper part of the steering wheel and with practically every control of importance within finger reach from the steering wheel. An arm on each side of the wheel operates on the right the direction-indicators, and on the left the headlamp-dipping, whilst on the end of each is a button which allows flashing of the lights during day or night driving. A rheostat is incorporated in the dash-lighting, there is a very convenient map-light in the large cubby-hole, windscreen washers are intelligently incorporated in the same control as the two-speed wipers and there is an electric petrol reserve switch with a warning light indicating when' it is in use. The new seats seem to me to be absolutely ideal for a fast touring car. They are sufficiently soft to be comfortable and yet the curved squabs grip one tenaciously under highspeed cornering. There is a particularly long movement forward and backward and the squab is also adjustable for rake. In conjunction with the telescopic steering wheel, a comfortable driving position should be found by all. Operation of the boot-lid (incorporating rear window) and the fuelfiller cap are from inside the car and the well-tried DB2-4 feature of the folding, occasional rear-seats, allowing use of this space for luggage when required, is retained. The benefit of this is fully appreciated on long distance touring. The support for the boot-lid, incidentally, is now controlled by a spring which is considerably more satisfactory than the strut previously used. New carpets have been fitted, making use, incidentally, of rubber reinforcement where most required.

arrange all the controls just exactly so, when it has been done, although, as with many other cars, I do not know why the mirror is not mounted on top of the windscreen, so that the left-hand wing is not partly obscured by it. When I came to start the car I immediately noticed that my recommendation made in the road test of the DB2-4 in May of 1957 had been implemented and the ignition-key now acts as starter as well. Its position is, perhaps, slightly awkward in that when the front window quarter-light is open there is scarcely room to twist one's hand to start. More seriously, this same quarter Internal improvements So much for the physical details of the latest Aston. A factor that particularly impressed me was that I recognised the car given to me to test as one which had had a lot of hard use by the works, before the installation of the special series engine. I should estimate that it must have done something approaching 50,000 miles ~nd yet the bodywork was in quite impeccable condition and free from rattles. This soundness of construction is borne out by my other experience of Aston Martin cars where their second-hand value is truly extraordinary. A very comforting thought this, when it comes to spending round about £3,000 on a new car! I am always impressed, on getting into an Aston, by the room inside the car, belied by the sleekness of the exterior, and the latest model is similar to its predecessors in this respect. A certain amount of difficulty is caused by manoeuvring long legs inside, but this is only to be expected in a lowbuilt sports car. A little bit of seat and mirror adjustment and everything is perfectly to hand. How simple it seems to arrange all the controls just exactly so, when it has been done, although, as with many other cars, I do not know why the mirror is not mounted on top of the windscreen, so that the left-hand wing is not partly obscured by it. When I came to start the car I immediately noticed that my recommendation made in the road test of the DB2-4 in May of 1957 had been implemented and the ignition-key now acts as starter as well. Its position is, perhaps, slightly awkward in that when the front window quarter-light is open there is scarcely room to twist one's hand to start. More seriously, this same quarter light can almost touch the steering wheel and bark the knuckles nastily if care is not used. A stop should be fitted to prevent its opening so far. On starting the engine, the immediate deep-throated rumble of the exhaust gives promise of many joys to come. Let me say, at this stage, that my only major criticism of the car lies in this exhaust noise. I am by no means pernickety about these things, and I expect a sports car to sound like one. But the special series Aston can produce a really thunderous roar and also causes drumming between 2,500 and 3,000 r.p.m. in the interior of the car. Apart from a certain amount of unwelcome attention which this may attract to a driver, it is liable to be tiring on long runs. However, it should be emphasised that this is a special series car and that it is engineered for the owner who requires the near-ultimate in road performance. Noise level can be reduced by generous use of the overdrive while cruising at anything up to 80 m.p.h., and I am given to understand that a more prudish silencing system would impair the extra power provided by the three carburetters.
Lighter steering As I moved off for the first time, I was immediately struck by the improvement in the steering. This has lost none of its delightful, sensitive feel, but it is lighter at low speeds. No doubt some of this is attributable to the altered steering design, but credit must also go to the Avon Turbospeed tyres which keep the steering light at low speed, handle well in wet weather, and are completely silent running at all speeds. The car takes some time to warm through thoroughly and a little pottering at slow pace demonstrates admirably the smooth characteristics of the engine. Despite high gearing and high compression, it is possible to go down to walking pace in top gear and still pull smoothly away if the throttle pedal is used sparingly.
Once really motoring quickly, the Aston comes thoroughly into its own. The gearbox is beautifully quick and positive and the overdrive switch ideally situated. Both clutch and brake pedal seem rather lighter than before-the latter due to the booster equipment. Over rough roads the suspension felt a little hard at low speeds, but tremendous controllability and lack of roll on high-speed cornering more than counterbalance this. I drove the car on both wet and dry roads and could find no cause for criticism in its handling qualities. The amount of power available, of course, dictates a sensitive use of the throttle under acceleration and cornering in wet weather or the back will go marching away in a gentlemanly fashion. The disc brakes were powerful and straight-pulling on both wet and dry surfaces.Speed testing When it came to attempting high-speed runs I was hampered by the all too familiar excessive amount of traffic, often behaving in an erratic fashion, and the apparent impossibility of finding a really long stretch of road with no unforeseen hazards. Consequently, I made no attempt to take a maximum speed timing, but from the performance of the car up to 100 m.p.h. and beyond it seems perfectly obvious that the manufacturer's claim of a maximum speed of approximately 125 m.p.h. is thoroughly justified. I had a car fitted with the lower 4'09 back axle ratio which limits maximum speed to this figure but provides the most exhilarating acceleration as the accompanying figures will show. In particular, I was delighted with the get-away from rest, which after a little practice I could regularly achieve to 30 m.p.h. between 3 and 3'4 seconds. It is very easy to promote excessive wheel spin but if the tendency to do this is resisted a remarkable improvement in acceleration times results. Gear change points fell rather awkwardly and resulted in a slight exceeding of the manufacturer's recommended r.p.m. limit of 5,500 for certain of the figures taken! For instance, the 0-60 figure suffered badly if the gear change took place at approximately 55 m.p.h. as it should have done. The effect of the increased power output on a car of approximately the same shape and dimensions is well brought out by a comparison of the figures I obtained on the Mark III special series and those I obtained on the DB2-4. It will be seen that the 0-100 figure, for instance, shows an improvement of over 3 seconds, and a notably consistent increase in speed was apparent right up to this figure. A feature of the performance, indeed, is that there is no " coming in with a bang" of power, but merely a smooth, progressive increase.
My feeling is that this is a worthy addition to a long line of fine motorcars. Not only is it the fastest series productionAston yet made (DB4s not yet accepted!) it shows an admirably logical (but all too rarely seen) profiting by experience. The gradual elimination of small faults over the years has resulted in a sports car that fulfils its purpose to perfection.

back to index

back to road test index

other fifties road tests:

Jaguar XK 150

Aston Martin DB2-4

other sixties road tests:

Chevrolet Sting Ray

Bizzarrini GT

Mercedes 230 SL

Porsche 904

Ferrari 275

Aston Martin DB4

other seventies road tests:

other eighties road tests:

Lancia Monte Carlo

Lamborghini Jalpa

Chevrolet Corvette

Author: ArchitectPage

Engine: Six-cylinder twin overhead camshaft. Bore 83 mm. Stroke
90 mm. Capacity 2922 C.c. (178.31 cu. ins.). Power output: 195
b.h.p. at 5,500 r.p.m. Carburation: Triple I~ in. diameter S.U. carburetters. Clutch: Borg and Beck 9 in. single plate hydraulically operated with
self-adjusting free pedal travel.
Gearbox: David Brown four-speed with spring-loaded reverse
stop. Laycock de Normanville overdrive.
Brakes: Girling hydraulic with hydro booster. Front: disc. Rear:
Alfin bi-metal drum.
Suspension: Front: independent, trailing link system. Rear: live
axle located by parallel trailing links and Panhard rod. Body: Aluminium panels on tubular steel framework.
General Dimensions: ft. ins.
Wheelbase... ... 8 3
Track (front and rear) 4 6
Overall length ... 14 3t
Overall width ... 5 5
Overall height ... 4 6;t
Turning circle ... 35 0
Fuel capacity... ... 15 galls 3 galls. reserve
Kerb weight.. 25~ cwt.
Performance: 0- 30 m.p.h. 3.2 sees.
0- 40 m.p.h. 4.8 sees. 0- 50 m.p.h. 6.4 sees.
0- 60 m.p.h. 8.2 sees. 0- 70 m.p.h. II .6 sees.
0- 80 m.p.h. 14.8 sees. 0- 90 m.p.h. 18.2 sees.
0-100 m.p.h. 23.8 sees.
Maximum speed: (maker's figure) 124 m.p.h.








Second Hand Car Test 1963

1958 ASTON MARTIN DB Mk III Convertible
PRICE: Secondhand £1,155; New-Basic£2,300~ with tax £3,451
Petrol consumption 19-23 m.p.g. Date first registered 1 February 1958
Oil consumption 100 m.p. pint Mileometer reading 20,816

COMPARISON with new models obtainable at the same price is always specially interesting when the more expensive used cars are being assessed. In the case of this
five-year-old Aston Martin, the price asked groups it among such new cars as the Morgan Super Sports, Austin-Healey 3000, and Renault Caravelle. Many buyers will never consider a secondhand vehicle, but others may be tempted by one of the most exclusive cars now available from the used car market at a third of its original cost.
Perfect engine tune is critical if the full performance available with this six-cylinder 3-litre unit is to be enjoyed, and in the car tested there were signs that the carburettors were in need of adjustments. Starting was poor, and there was a tendency to fluff and misfire even after many miles to warm through; a contributory factor is that the engine is running a little more than 60 deg. C. according to the car's thermometer. In spite of this, performance figures taken with the used example compare quite reasonably with those of the model when new. Oil pressure is about 50 p.s.i. in normal use, but drops to nearer 20 p.s.i. after a spell of really hard driving, when slight main bearing" rumble" is audible on acceleration. These pointers suggest a fairly high overall mileage, certainly more than the total given in the data, but it was felt that there was still a good run of life left in the power unit.
On the road, the acceleration is most gratifying, and third
gear in particular pulls the car vigorously up to the 90 m.p.h.
mark on the somewhat optimistic speedometer. The synchromesh on the three upper ratios is effective, and the indirect gears are quiet except for some gear lever vibration at high revs. Overdrive was available as an extra for this Aston model at more than £100 including tax, but had not been added to this car. Clutch take-up is smooth, and acceleration testing did not provoke any clutch spin.
Steering heaviness in manreuvring changes when on the move to pleasantly light and accurate control, which gives confidence in fast driving; and, of course, the finely balanced roadholding and excellent ride comfort remain much as standard. The;: only exception is that bad potholes provoke a considerable jolt, r~sulting in some rattles from the hood and body structure, and it may be that the dampers are now slightly weak.
For such a fast car, the bnkes, with di:;cs at'the front only, and no servo assistance, ar(: rather .lacking in response unless very heavy pedal effort is applied, when there is then some ten
dency to tyre scream. At high speeds the brakes feel more responsive, but there is certainly need for a servo. The handbrake, controlled by an " umbrella" handle beneath the facia, is ineffective, and will not hold the car on a steep gradient.
Except for the spare, which is a well-worn Avon Turbospeed,
all the tyres are Dunlop RSS. On the front wheels they are new, but those at the rear are almost due for replacement. There is a neat and almost complete tray of tools in position under the bonnet, and the car also comes with jack, wheel nut hammer and a well-used cover for the folded hood.
A complete respray has been carried out to a high standard but the colour ~hosen-bright green-seems an unfortunate choice for a car .of such distinction, which would have been better suited by more subdued colours. It is understood from Ken Jervis Ltd., who carried out the respray, that the colour was supposed to be a metallescent shade, flecked with gold, but the metallescence has not shown through. The chromium is reasonable for the car's age--considerably scratched but wellpolished and shiny. Underbody examination revealed no serious age deterioration, and the exhaust system is sound. The hood is in beige, and appears in good and uncreased condition, but the quarters on each side have come unstitched and flap noisily above
60 m.p.h. .
Interior condition is fair, and although the maroon leather of the seats and door trim looks well-used it is not too dirty, and the seats are comfortable and give good support. This is one of the few sports cars to offer comfortable occasional rear accommodation with adequate headroom for two adults. The beige carpets and facia trim look rather drab and well worn; replacement probably would be justified for a car at this price.
Except for the headlamp flasher bulton, and the excessively vague and optimistic fuel gauge, all the equipment is in good working order, which includes the clock-keeping good time. The new owner should enjoy many of the fine qualities which made this one of the most sought-after convertibles, and provided he remembers that he is buying-for just about the original amount paid in purchase tax-a car which probably has seen considerable use, he should not be disappointed.

(Figures ill brackets are those of the saloon Road Test with overdrive, 27 December 1957)
0 to 30 m.p.h. 4.2 see (3.5) 0 to 90 m.p.h. 23°9 see (22.3:
Oto50m.p.h. S.Osee (7.1) Oto 100 m.p.h. 3204sec (31.0)
o to 60 m.p.h. 11°5 see (9.3) Standing quarter-mile 17.5 see (17.4)
o to 70 m.p.h. 14°5 see (13°1) 20 to 40 m.poh. (top gear) 6°3 see (7.8)
o to SO m.p.h. IS02 see (16'7) 30 to 50 m.p.h. (top gear) 5'S see (7.4)
Car being sold by Ken Jervis Ltd., Cobridge Road, Hanley,
Stoke-an-Trent, Staffordshireo Tel: Stoke-an-Trent 21782