REFINENT OF RUNNING AND EXCELLENT PERFORMANCE

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THE 12/70 H.P. ALVIS SALOON

UNQUESTIONABLY, the Alvis is in the thoroughbred category. Ever since T. G. John introduced his four-cylinder light car just after Peace broke out, the Alvis has been a marquethat-mattered, to those who really understand cars, as distinct from those who just drive them. Fame came to the Coventry firm after the 1923 200-Mile Race, and ever since the range of models—through the front-drive cars and various ” 12/50s and ” 12/60s” to the existing sixes and the ” 12/70″ four—has maintained a high status in the automobile scheme of things. Alvis reputation having been established, and largely maintained, by I /litre four-cylinder cars, we were naturally anxious to try the latest Alvis ” four,” in the form of the 12170 h.p. 1,842 c.c. model, a car which so very well emphasises the ability of a modern fourcylinder engine to do what only a ” six ” could do in the era prior to decent carburation and properly understood flexible mounting. Several writers, apparently swayed by tender memories or extended associations with the old-school ” 12/50,” have attempted to compare the existing fourcylinder Alvis with this model. Although MOTOR SPORT is as enthusiastic as any other paper over the earlier ” fours” of this marque, of the approximate period 1925-32, we feel that it is wrong to suggest that the modern ” 12/70 ” is a presentday version of these earlier models. Actually, the type represented by the 1925 four-cylinder Alvis is, to-day, almost absent from the new-car market, and, in our opinion, exists, categorically, only as the super sports marques of Alta, Atalanta, Frazer-Nash and H.R.G. That is not to suggest that the Alvis has not all the good and essential qualities looked for by the sportsman. There is available at the present time a number of admirable cars, which provide, as we on this paper have continually emphasised, closed car convenience and dignity, possessing such desirable features accurate steering, good high output engine’s and remote controls. Let us suggest that, if the Alvis be placed in this class, rather

in the sports-car category, then at least it has to be placed very high on the list, having far finer qualities than most others of like type. Thus it will be appreciated that the famous Coventry firm has produced-a most interesting car and one that justifies the price at which it sells. Quite a short run in the “12/70 ” emphasises the extreme refinement of the car—silent engine, quiet bodywork, and supple suspension. Add to these not common characteristics excellent performance, high speeds on the indirect gears and high quality detail work, and you begin to see the Alvis ” four ” in its

true light. It is true that cars of the category in which we have placed the Alvis are usually capable of useful average speeds, and this is especially so in respect of the ” 12/70,” as the first evening’s journey emphasised. Leaving London in rather a flurry, as the car arrived from Coventry about 1 hours late, we took a reading at Croydon Aerodrome and recorded an average of rather better than 45 m.p.h. to Lewes, Sussex, by stop-watch timing. The driver was most emphatically not conscious of being” on the job,” and, indeed, kept up conversation with his three passengers throughout, while we made several brief stops (deducted from the total time) which, as every fast driver knows, are not conducive to a good average on a short run. Thus, early it was obvious that this Alvis had the average speed propensities

of far bigger motor-cars. Incidentally, during this run, Tilburstow Hill, approached at 50 m.p.h. in third gear, was breasted at 48 m.p.h. on this ratio. The driver sits well up to a nicelyraked steering column, though on the car tested the bucket-type driving seat proved unwilling to hold fast in the fully forward position. The steering wheel is thin-rimmed and has a standard centre, with direction indicator control at the top, ignition advance and retard to the left, and headlamp dimmer control at the base, with central horn push. These minor controls, and the pull-out switches on the facia, reflect the car’s high quality. The remote central gear-lever is long, slender, and very pleasantly situated, so that the driver finds himself automatically resting his left hand thereon when only one hand is required for steering. The right-hand brake lever is set well forward of the off-side door and is rigid in the real old-school tradition (with a lever ratchet release, which functions very smoothly), automatically falling forward when released and holding the car

securely. It is necessary to stoop forward only very slightly to reach it. The screen pillars are not unduly thick and the near-side sidelamp is just visible from the driving seat. The bonnet view is rather plain, even reminiscent of another make, and we suggest reinstating the Alvis bunny mascot on the fiat filler-cap. Here we may digress to say that the solid radiator shell with its external filler cap, the tapering bonnet, and rugged build of the nicely contoured rear luggage compartment, stamp the Alvis as a car of good breed externally. Returning to the driving compartment, the pedals are very well spaced, clutch and brake on the same plane, and accelerator, which has a noticeably light action, well isolated on the right. The facia carries, from left to right, a large cubby hole without lid ; a pull-out ash-tray ; speedometer with inset clock ; panel lighting switch above ; starter switch below ; hand-throttle ; dynamo window above ; ignition key and three-position lighting switch below ; combined radiator thermometer, fuel gauge, oil gauge and ammeter as a large dial to balance the speedometer ; choke below ; fuel supply warning lamp, and reserve fuel control. All the dials are easy to read and at night they are very brightly illuminated, though without actually dazzling the driver. The fuel gauge and thermometer are. electrically controlled, both ceasing to register when the ignition is off. The latter normally registered approximately 55°C., going momentarily to 70°C. at Brooklands, but was not reading correctly, the normal temperature being 70°C. The normal oil pressure was 75 lb. per square Inch. The fuel gauge seemed accurate, but does not show the quantity in reserve, and the too-bright warning lamp flickers on early, though staying alight continuously when the reserve is in use. Twin, almost inaudible screen-wipers, with separate controls and remote motor, are fitted, likewise twin anti-dazzle visors. The screen winds partially open, and the roof slides back, with rather a stiff action. Ventilative arrangements are adequate. The horn note is rather harsh but effective, the rear blind works well, the big rear window is useful for reversing, in conjunction with a gear-lever-operated reversing light, and the central rear-view mirror is very adequate. There are no pockets in the doors, which shut and

lock effectively. The clutch pedal is most conveniently cut away to allow one’s foot to rest on the floor. So much for first impressions gleaned from the driving seat. We can now con sider road impressions. The clutch is not heavy to hold out and needed care if considerable judder was to be avoided in moving off from rest, but it is essentially positive in engagement and the pedal as a short travel. Subsequent clutch spring adjustment obviated this tendency to judder and lightened the action. The gear-lever has the usual locations. Reverse is forward, beyond and outside the firstgear position, with no catch. The lever moves rather stiffly and has a rubber draught-proof cover. The synchromesh on second, third and top gears is very effective unless hurried unduly, when it is possible to miss engagement or to provoke considerable grating, which, however, can be obviated by double-declutching for downward changes. The changes go through quite quickly and the lever has a short travel and stands very brutal movements. Sometimes it was distinctly

difficult to locate first and second gear positions when stationary. The lower gears are commendably silent, emitting only a very low high-pitched whine, and third is virtually like top. This is fully in keeping with the whole tone of the car, for the ” 12/70″ essentially performs in silence. Although the engine sounds noisy, and the tappets are audible, with the bonnet open, none of this sound reaches the occupants, and in consequence one can cruise indefinitely at 65 to 70 m.p.h. without any sensation of effort beyond carburetter roar of a mild order when regaining speed after a check. Certainly this is one of the most silky ” fours ” we have sat behind and only right at the rev.-limit does any distress become apparent, in the form of fairly pronounced valve bounce. The carburation is clean throughout, an occasional spit-back having no ulterior effect. One is profoundly impressed by the ability of the engine to maintain its surge of power to usefully high speeds on the indirect ratios. Without having thought anything about the Alvis’s manner of running regarded as a whole, there is created the impression of a car which motors briskly with a commendable lack of effort. Other features fall in line to enhance this pleasant ability. The suspension is very supple, so that the car rides smoothly over had surfaces, not a trace of shock reaching the occupants. Indeed, over a test road it shows up nearly as well as certain Continental cars with independent springing. On fast corners a good deal of roll takes place in consequence, though the Dunlops do not protest. Apart from this the Alvis is very stable, swinging into fast bends and out of them with no unexpected changes of direction or “feel.” This supple luxurious running is emphasised because there is nothing ” dead” about the riding, the lamps and bonnet displaying movement over rough surfaces, and the front bumper purposely being arranged as a stabilising agent. Tail slides were extremely difficult to provoke. The bodywork, save for an occasional squeak, and a drumming from the region of the speedometer at over 65 m.p.h., was absolutely quiet, nor is there much wind-noise. Reclining in the leatherupholstered very spacious rear seat, at upwards of 70 m.p.h., the ” 12/70″ conveyed a fine impression of fast travel in

considerable luxury. Pitching is only provoked by very consithrable undulations and is very quickly damped.

When idling, the flexible mounting of the engine is evident by considerable movement through the gear-lever, clutch pedal, and, to a lesser extent, the steering column and upper part of the facia.

The steering has a high degree of accuracy, and is light and smooth at speed. The ratio is fairly low, the wheel needing 3+ turns, lock to lock, and the castoraction is sometimes slow unless initially assisted. On acute bends a rather more consistent castor-action or higher gearing would be appreciated, and there is a suggestion of lost motion and sponginess. The lock is good and only very slight trace of return action was evident through the wheel, varying with road roughness. In general, and particularly as regards light smooth action, it is good steering. There is very slight column movement. A trace of heavier action is noticeable in holding a course round long bends. The brakes are extremely well able to cope with the speed of the car and work very progressively indeed, demanding only a very gentle pressure for ordinary stops. This progressiveness required

getting used to, as at first we thought the brakes unduly fierce through standing too heavily on the pedal. They work with no more than a low and pleasant hissing sound, or slight tyre squeal if heavily used, and remained immensely powerful right to the end of the 490-mile test. There seemed to be a slight tendency to pull the car over out of line, applied hard at speed, and to lock the front wheels on loose corners, but we were never really troubled on this score. The nose dips under ” crash ” stops, but the braking is commendably smooth.

On the gears one would normally change up at about 20, 30 and 40 m.p.h. respectively, but the Alvis goes most usefully up to 55 m.p.h. in third in dealing with tricky traffic situations, and at Brooklands we attained actual (corrected) maxima of 25, 41 and 59 m.p.h. During our first visit to Brooklands a flooding carburetter and fuel starvation spoilt the first set of figures, though in this condition the flying half-mile was covered at 74i m.p.h. and a lap at 70.6 m.p.h. We agreed to try the car again and it was returned to us with these faults cured, and with the engine decarbonised. The latter attention made it almost unnecessary to move the ignition lever from the fully advanced position, using B.P. Ethyl, whereas previously pinking was evident, particularly on straight petrol, and could not be completely cured by retarding. The Alvis displays little loss of power with retarded ignition. Lots of hard driving on Brooklands failed to raise the temperature from its steady 70°C. reading, nor did the oil pressure vary, and the silence of running was most notable. The car liked to find its own course on the Members’ Banking and at rough sections of the track the movement of the front wheels could be felt, but not entirely controlled, through the steering. There was some tendency to wander, on account of the gale that was blowing, ‘which had put a stop to club flying. On the sheltered part of the track, beneath the protective slope of the Byfleet Bank ing, we covered a flying half-mile at 77.0 m.p.h. The flying lap was covered at 74.3 M.p.h., two up, against a very heavy wind blowing up the Railway Straight. The highest speedometer read

Lug was 83 m.p.h., representing a 6 m.p.h. optimism at full speed.

Turning to acceleration figures, to 50 m.p.h. occupied 15.2 secs., but the Alvis works driver put the figure down to 14.6 secs. Our own time from to 60 m.p.h. was 23.2 secs. That this good acceleration is constant and well maintained is shown by the accompanying graph, giving readings plotted every 10 m.p.h. from a steady speed of 10 m.p.h. Some clutch slip was evident when making snap changes on these runs. The interior of the car remained free from fumes with all windows closed for speed work.

In spite of its ability to perform briskly, the Alvis has excellent top-gear abilities low down and sharp corners can be negotiated in top if desired. In third gear the bite becomes evident over about $0 m.p.h. Fuel consumption worked out at approximately 24 m.p.g. in fast driving on the road and at approximately 23 m.p.g. during town running and the

Brooklands tests. The tank holds 11 gallons, providing a range of about 260 miles. The headlamps are adequate for rapid night driving and on difficult roads after dark 70 m.p.h. was held for several miles. At 60 m.p.h. the Alvis settles down to cruise in silence, road inequalities smoothed out most effectively. This speed is very pleasantly regained after temporary checks by reason of the car’s ability to run easily and quickly up to 50 m.p.h. in third gear. Normally, second gear is used for starting from rest. The rear seat has useful inconspicuous

arm-rests. The propeller shaft tunnel does not hamper the rear seat occupants, and entry and egress, even from the driver’s seat, are unimpeded. When one meets another ” 12/70,” as we did more than once, one appreciates the wellbalanced build of this saloon. It looks neither too large nor too small, and has an air of dignity allied to speed. The radiator grille adds unconsciously to this impression. Under the bonnet the oil filler is accessible as a large cap in the valve cover and the sump level is ;ascertained by a float-type indicator. The radiator cap is external. On the near side are the combined manifolds and

the big air-cleaner for the Solex carburetter. The windows wind effectively and have anti-rain panels. Triplex laminated glass is used for the screen, Triplex Toughened glass for the windows. The spare wheel lives in the big locker. The four doors hang from the central pillars and small old-style ventilators are provided in the scuttle sides. Coming to the specification, the fourcylinder 73 x 110 mm. engine (1,842 c.c.) is claimed to give 63 to 64 b.h.p. at 4,250 r.p.m. It has push-rod o.h.v. closed by double valve springs. The combustion spaces are of lozenge formation with in

clined plug entry. The two-branch light alloy intake manifold is hot-spotted by the three-branch exhaust manifold. The three-bearing crankshaft is fully balanced. The light alloy sump is ribbed for cooling. The cylinder blocks are cast in the Alvis works and weathered in the open in the old-school tradition to ensure long cylinder life.

The drive passes via a single plate clutch to the four-speed and reverse gearbox which has synchromesh engagement of second, third and top gears. The frame is of tubular-braced box-section type, underslung at the rear. Suspension is by half-elliptic springs and the brakes are Bendix-Cowdrey with 11″ x lt” drums. A Marks double-roller steering box is used. The aim throughout the design has been long retention of high performance. The chassis weight is 17 cwt., a notably low figure for a 1.8-litre car of over 8′ wheelbase. Equipment includes Smith’s instruments, Lucas electrical equipment and Dunlop covers.

In conclusion, the four-cylinder Alvis is a notable addition to the ranks of smallengined high performance closed cars that handle as an enthusiast would wish. Moreover, it is one which conies rather in a class of its own by reason of combining silent engine, silent gearbox, smooth braking, high quality bodywork, and ability to attain high speeds on the indirect gears, in a manner which stamps it unmistakably as a car of great refinement as well as one of modernistic specification and performance. The saloon is priced at -/.435 and full particulars and demonstrations will be supplied by Messrs. Alvis Ltd., Byron House, St. James’s Street, London, S.W.1 (WHI 8506).