THE HONGKONG TELEGRAPH.
OLDSMOBILE SIX
ODUCT OF GENERAL MOTORS
111-Inch Wheelbase-19.84 H.P. (RA.C. rating) — 185 cubic inches piston displacement-1928 models.
Dickey-seat Roadster
4-seater
G.$1,175
Touring Car
5-seater
1,175
Q
Sedan (2-door)
5-seater
1,250
Sedan (4-door)
5-seater
1,350
All prices subject to change without notice. Keen appreciation has grected Oldsmobile's smart now beauty. Naturally such modish lines and striking colours would win the lion's share of admiration from those who know it only by sight. But every day Oldsmobile perform- ance seizes the attention of those who never knew it before- because you can't know till you drive the car. This thrilling, smoother performance is the crowning feature of Oldsmobile-the overflowing measure of value now yours at prices lower than ever before.
THE DRAGON MOTOR CAR CO. LTD.
Telephone Central 1246 or 1247.
38 WONG NEI CHUNG ROAD,
HAPPY VALLEY,
ONLY TWO
Only two makes outsold Chrysler last year. These two have been in the business for nearly a quarter of a century. Chrysler has risen from 27th to 3rd Place in 4 years.
See the Chrysler at
A. LUNG & Co.
Showroom:
19, Queen's Road, Phone C. 1219.
SERVICE STATION:
PERCIVAL ST.
WANGHAI.
1928 E. W. DOUGLAS
ANOTHER SHIPMENT, HAS ARRIVED of the Famous 1928
E. W.
DOUGLAS
See them and be convinced of their wonderful value.
"THE DOUGLAS FOR DEPENDABILITY
1.
Enquire about our Hire-Purchase System. ALEX. ROSS & CO.
Prince's Building,
2nd floor, Ice House Street, Entrance,
MOTORING SUPPLEMENT., SATURDAY, MARCH 17, 1928.
ISOLATING ENGINE
VIBRATION,
How Manufacturers Lay a Ghost.
Engine vibration has always been one of the worst enemies of the
MOTORING AND TAXATION.
Parliamentary Petition for Petrol Tax.
In order to impress upon Parlia-
automobile designer and if the fooment the urgent need for the drastic amendment of the present has been driven further into the system of motor taxation, the background, even to-day he has not Automobile Association has or- been entirely beaten. Vibration is like an assassin, it skulks in the ganised a Petition to Parliament background, and creeps out at awk-to be signed by all owners and ward moments. Also its effects are users of motor vehicles. 'diflcult to measure, and a commuo- ity of little vibrations can get into step together and by pushing at the right moment can make an other wise innocent mass of metal behave like, a roguo elephant.
Through the medium of its 350,000 members, and other chan- nels, the Association hopes to in- duce Parliament, at an early date, to repeal the present system and substitute, a method by which overy, individual motor owner will be taxed in proportion to his road: use.
There are many forms of flexible or cushion mountains introposed between the engine, or engine and gear box unit, and the frame of the In the experience of the AB- ear, and most of them can defuite-sociation; the present lump sum ly be shown to give beneficial fe tax has been arbitrary In its sults. But from this fact it does operation, unjust in its incidence" not necessarily follow that Bexible and irritating to the taxpayer, mounting is a necessity; all that is and Parliament is urged to adopt really, proven is that on some para flat rate pelrol tax as the basis ticular car a given form of mount- by which the revenue required ing prevents certain vibration from from motorists should be raised. being so acutely noticeable. Whoth- er or no the source of vibration should be existent in the first place is quite another matter.
Cases of the Trouble. With these facts borne in mind it is easy to see why some designers are all in favour of flexible mount- ings and others equally-strenuously opposed to them. So far as major vibrations are concerned the flex- ible mounting is a cure, and not a prevention.
Among the objections which would be overcome by the petrol inx are:
(n) It is collected by a method which entirely ignores the extent of road usage, dex- pite the fact that the tax was originally imposed sole- ly for road costs.
(b). A great number of owner drivers who are only able to
• use their cars occasionally or at weekends are unduly ponalised by having to pay the same tax as those are using their cars сол Linually.
who
The payment of a lump sum lax in advance presses hard ly upon motorists of moder- kle means.
(d) The keeping
What are the chief cutises of en- gine vibration? In simple language they fall into two main classes. First there are mechanical causes such as lack of balance and relative(c) movements like spring or whip in component parts, and, secondly, the reactions from compression and ex- - plosion forces. Under the mechani- cul classification, in the four-cylin- der engine theoretically the primary inartin forces due to the movements of the pistons and 'connecting rods are balanced, but the secondary forces due to the movement of the mean centre of gravity of the pis- tons are not balanced and give rise to a vertical vibration.
Both primary and secondary forces are balanced in the six- cylinder engine. Four-and six- cylinder engines are liable to vibra tion caused by torsional whip In the crank-shaft, the six more than the four, partly due to the longer shaft, From the valve gear drive, cam nction, magneto drive and other causes all sorts of minor vibrations, mostly of high frequency, are caus -ed..
Producers of Acute Discomforts. Under the second classification of reactions from compression and ex- plosion pressures is to be found different source of vibration, and it has only recently come to ba fully appreciated that these vibra- tions are much more, productive of discomfort than those caused under the mechanical heading.
of reserve vehicles is discouraged, na the person owing two cars, only one of which is on the road at a time, is compelled to pay full tax on both cars. (e) Large numbers of second- hand cars which-with tho petrol tax would be occn- Alonally used, are lying idle throughout the country, be cause of the liability to heavy taxation immediately they are taken into use: The Automobile Association contends that the case for the petrol tax has been proved up to the hilt, that there is little or no dimeulty in defining motor spirit for the purposes of taxation, that the possibilities of the tax being evaded are remote, that theoretical objections of this kind have been exaggerated out of all proportion to their real importance, and that-given the Koodwill of the Authorities-a flat rate duty is a practicable and sound basis for the equitable taxation of motor owners.
un-
quency vibrations and tremors set Possibly the realization has been up in the engine itself; there is no brought about by the immense im- intention of dealing with provement in design and manufac balanced secondaries or with torque ture of the mechanical parts of the reactions. The same form of mount- engine, which improvement has fre- ing is applied to the gear box, and quently failed to eliminate vibra- is equally effective. The feature of this type of mounting is the use tions originally attributed to me of rubber insulation without metal- chanical causes, so that suspicion has been east in other quarters.lic contact, even through the secure This, incidentally, is the real reasoning bolts, and it is now extensively why the six-cylinder engine has used on cars of high quality,
often failed in practice to make Another form is that applied to good the great superiority which it is held theoretically to possess over the four-cylinder.
and originated for the 14 h.p. Hill- mari car. In this, flexible rubber buffers are used, and the engine is Many motorists must have able to awing through a very small noticed on certain cars that quite as movement with the object of damp- much vibration seems to arise from ing torque reaction. To prevent the engine during over-run-that engine oscillation a frictional band- is, when the accelerator pedal is re-type shock absorber is interposed leased and the car coasting and between the engine head and the driving the engine round-as dag:board structuró. pulling the car. This vibration is observable at quite low speeds, whereas out-of-balance mechanical vibration gets much worse as the speed increase.
Cause of Vibration.
The Use of Rubber,
Then a number of cars have rub- ber blocks, bushes, or strips inter posed between. the mounting and the frame, but the securing bolts are not insulated,
The cause of the vibration now under discussion can usually be One of the most interesting of traced to unequal volumes of com- the carefully developed arrange- pression space, and therefore un-ments is on the Rolls-Royce, where equal pressures in the various cylin- there is on each side of the engine ders, and to unequal explosions from at the front a damper of the fric- the same cause. In addition,, the tional shock absorber type, built in least.Inequality in the distribution for the purpose of absorbing the re- of equal amounts of explosive mix-action from torsional vibration. In dure to the cylinders through the the crankshaft.
induction system will cause fur- Quite a different principle is ap- ther courseness of running. It may plied to the six-cylinder Ruver car, be possible to damp down this form the engine being mounted on short of vibration by means of flexible laminated springs wrapped round mountings, but it is naturally bet- ter to endeavour to prevent them the frame members. The object is to give a cushioning effect in the from arising in the first instance, drive. A laminated spring of the From the foregoing generalities transverse type is used to carry the it appears that flexible mountings front end of the four-cylinder can themselves be classified accord- Chrysler engine, whilst on the ing to the work which they are ex- Chrysler 70 engine the bearer arms pected to perform. The most simplc, are attached to brackets insulated and incidentally a very effective, from the frame sides by sheet Tub- form was originated by the Alvis ber.
:
"
FIAT
FIAT 509 ci
YOU THEDE CAD ALWAYS GETS YOU THERE and BACK WITH SPEED, SAFETY & in COMFORT.
"Unprecedented Value for money'
London Morning Post.
From $1850
The Car of International Reputation.
Sole Agents for Hongkong; Canton and Macao SOC. ITALIANA, IMP, ESP, ESTREMO ORIENTE, LTD.
Managers:- A. GOEKE & COMPANY.
SHOWROOMS AND OFFICES 67, Des Voeux Road C.
Tel. C. 4821
FIAT 509
FOR 1928
WORKSHOP
67, Des Voeux Road 0.
NOW ON SHOW.
Tel. C. 4821
NEW 1928
PONTIAC is Here.
SOLE AGENTS:
A. LURG Ở C
18, Queen's Road C.
RUBBER REPLACES
SPRINGS.
Company; it consists of mounting. An interesting system has been the bearer flanges of the engine be-employed on the 14 h.p. Humber. tween a series of six double conical In this case the engine fect are An English Invention. rubber buffers, the latter being mounted on stiff compressional coll
7
Tel. C. 1219.
The latest invention of W. Law-rubber cushion which fits in bes son Adams, British engineer, a set tween the two discs when they are of two steel discs enclosing a rub" bolted together, ber cushion, It is claimed.will make such a trip possible.
This device has one steel disc
As the car passes over ruta or Irregularities in the road, this rub- bor cushion absorbs the impact from the teeth of the two steal discs.
In a test over a water-worn, poti
bolted to the frame so that the springe, capable of being adjusted, London, Feb. 4,-A pleasure trip mounted on the frame of the auto metal of the engine does not direct and on ball apring loaded frictional over the roughest country road, mobile. Another dise. similar to ly or indirectly touch the metal of devisices. To prevent oscillation of chuck holes at every six feet, minia the first is connected to the end of the frame. The object is to provide the engine due to torque reaction ture mountains and valleys and the axle by a heavy steel arm. Both holed road; a car equipped with a rubber insulation which can abn Hartford typo shock absorbed is never a bounce or folt, in un auto discs are toothed, the tooth meshing, these springs traveled 40 miles an sorb or damp all the tiny high-fre- fitted at the top of the engine.
without springa!
into similar teeth on a soft soft hour in comparative case:","r