AU GUS'I 221' 1' 1 J.YUl:S

THE AUTOCAR 1\ Journal publighe~ in tbe intereata of tbe mecbantcall\? propeHe~ roa~ caniage.

EDITED BY H. WALTER STANER.

No. 670. VoL. XXI.] SATURDAY, AUGUST 22ND, 1908.

[PRICE 3D.

The Autocar.

:Published Weekly.)

Registered 4S a newspape~ for transmission in the United Kingdom.

Entered as second-cla.~s matter in the New York (N.Y. ) Post Office.

£ditorial Office :

COVENTRY.

Publishing Offices :

20, TUDOR STREET, LONDON, E .C., England.

CONTENTS. N OTES USEFUL H1 :-lTS \ NO TI PS (ILLUSTRATCD) RADIATOR EFFICIENCY }NVESTIGATJONS (IL LUSTRATED) .. A H YDRA ULIC J ACK ([ LJ.USTR.i.TCD) .• M OTORING P 1tENOMENA . •

PAGE . . 28 1-282

283 . . 284- 286

287 288-289

Low MoTOR C AR T RAGF.D IES ARE l\lADE-H ORSF. J USTICE-MOTOR

LAW

289

THE :20 H . P . T.T. R OVER CAR ( ILLUST RATED) ·O N TH E. T RAC K • • ROYAL A.C. ASSOCIATES .• THE F ouR~lNCII R ACE ..

A NOTHER SUCT ION GOVERNER . . ls LE OF M AN COURSE Co~HOUR .. ON T H E ROAD. 13v Ow c:N J o1-1N SMAL L C AR TA LK • • -CAUSE A N D EFFECT-O[G:-IITY AND bt ?U :: >i;.: NCE F ERRYING MOTOR C ARS I N SCOTLAND . . A STUDY OP STEE.R I NG (ONNF"CTIONS . . EXCITING P REJUD l CF.

( QRRES 8 0 ND E NCF. • • AERONAUTICS {I LLUSTRATED) • . MoTOR C AR A cc10E:-JTS FLASHES .• < CLUB D OINGS REVIEWS • •

. . 290- 29:2

293 293 294 294 295 296- 29 7

298 299 299 . . 300- 301

30,. 303-306

307 · · 308-3 II

3 1 :2 - 3 14 3 I 5-316

116

Subscription Rates ;

Briti sh Is les 16s. Abroad (thin paper edition), 22s . 8d . per annum.

.I Notes. Engine Efficiency Overdone .

It appears to us that there is a ?ang~r. of engine --efficiency being overdone. E ve ryone 1s stnvrng now to see how much he can possibl y get out of an engine of a giv~n size. This is a most praise\\·01thy 11·ork, and one which we have ahrnys encouraged to the utmost. In fact it may be sa id th at a ll hill clim bs, ra ces, and tests on the brake are instituted with a vie"· to getting as much as possible out of an engine. In all these things -there is a limit beyond which it is not practical to go. An engine can be so made and adjusted that it will develop an enormous power for its si ze, but it will neither run nor pull slowl y, and it becomes to all intents .and purposes a racing engine; marvellously efficient for i.ts size, but a most uncomfortable engine to put into an -ordinary touring car.

Tn the first place it will be very diffi cult to start owing to its high compression. and in all probability to it s carburetter. 11·hich , to ensure a suffi ciency of air at high speeds, often gives too much air at starting. In the second place when once started it is a bsolutely impossible to make it run slowly when the clutch is out. and when it is in it bangs, and spits. and jerks, unless it can be allowed to run at so high a ~p eed th at to humour it , one must frequentl y put in the third or even the second sp eed 1rhere with a less feroc ious and less efficient engine one 1rnuld be using the fourth . Within wide limits the car can only be controlled by taking out the clutch or shutting the throttle dead; there is no graduation. The engine is either working like a Trojan or not working at all.

Now wh at is wanted is the happy medium. It is not diffi cul t to buil d an engine th at will run quietly and pull well at low peeds, and many can make an engine which will run fast and de1·elop a remarkably high power at high speeds, but a fter a ll the best engine to drive is the one 1rhich is not o nl y q uiet and ?mooth pull • i11g· at low . peeds, but whi ch a lso on occasion will develop ve ry hi gh pmrer. We ha1·e not much hesitation in . ay in g th at in t he majority of cases th t' best engines to d ri1 ·e are those which do not depend ton much upon an exceedingly high ra te of re1·olution for their power. As an example of what we mean we may t ake two eng ines at random ; say th at one is 3in. bore and the other 4in. "\Tow by running the smaller engi!w at a very hi o- h speed it can be made to de1·elop qmte enough power for an ord in a ry small four seated ca r. The 4in. engine 11·ould , of course, be proportionately mor powerful at the same engine speed, but the fact of the matter is there is practica ll y neve r an y need to push it . so that it need not be designed or adjusted to give such an extreme po11·er fo: ij s size as is necessary in the case of the smal !er engin:V,.

Some Suggested Tests . It shOLtld be clearl y understood ire a re not advocating the buikling of big slugg ish engines again st th at nf small an ,. l exceediegl y powerful hi gh spee~ engines, a_s a sluggish engine, whether big or ]jt_tl e , 1s _not wort l1 driving. What we want 'to call attention to 1s the_ fact that great power for a gi1·en si ze is not necessa ril y a proof th at the engine develop i1~g it is rea ll y the bfst to drive a motor car. Like a lmost e1·erv other part of a car the engine and its adjustmen'.s constitute_ a compromi se . As matters stand, 1Ye t_h111k that rac111g_ an rl hill-climbing provide plenty of evidence as to effi ciency in relation to size, and we shoul d like to see both th < ' Royal Automobile Club and the Society of Motor Manu· facturers come to some ag reement as to a standard form of brake t est . In onl y o ne in stance of late among the exampl es whi ch have been gi ven of high effi ciency for size rlo we remember that the power deYeloped at lower speeds has al o been made public. It is all _ ve ry well to know th a t an engine will develop ~ t~rn~ c horsepower at 2,000 r.p.m. a minute, but if 1t. 1s to be pleasant to drive, we al so want to know what it develops at much lower speeds, and therefore all the,:;e tests . houlcl be p rogressive.