An article, first published by:

Motor Cycling
Wednesday, April 17, 1935
pages 764 and 765

All-round Motoring with a Road-Going Supercharged Twin

How an Ordinary Big Twin Morgan Reacted to Blowing

Henry Laird's Super Sports Morgan

The supercharged Morgan J.A.P. which looks very little
unlike a standard model. Note the outside gear change.
It is, of course, a two-speed machine.

A MACHINE that combines the docility and flexibility of a fluffy side-valve with the performance of a T.T. 500 and the acceleration of a dirt-track twin sounds altogether too good to be true - in fact, "the ideal model" hot from the Correspondence columns.
Yet such a machine actually exists and is used daily on the roads of Derbyshire and elsewhere. Its engine is an ordinary 1,100 c.c. water-cooled o.h.v. J.A.P. of 1931 vintage, and the machine itself is Mr. Henry Laird's Super-Sports Morgan. The Morgan's remarkable characteristics mentioned are all derived from the fitting of a Zoller compressor and it can therefore claim to be the only road-going big twin which is "blown."
In the past, of course, and at present too, supercharged engines have been used on the track, but they represent very different jobs to Mr. Laird's J.A.P., which, as well as being used on the road, has taken him successfully through many trials in different parts of the country; in fact, Mr. Laird has used the machine for general all-round purposes. He is, of course, a director of M.A. McEvoy, Ltd., the famous Derby supercharger manufacturing concern, and can, therefore, be accepted as one of the leading authorities on supercharging in this country.

A Straightforward Job

There is absolutely nothing "trick" about the Morgan; the blower is anchored on the near side of the crankcase and is driven by means of a chain and countershaft. In a quick survey of the machine it is quite possible that the "blower" would be missed altogether - so unobtrusive is it. It blows mixture to give a theoretical maximum supercharge of 12 lb. per square inch, and it was found possible to raise the top gear of the two-speed chassis from 4.5 to 1 to 3.8 to 1 without losing anything whatever on top-gear acceleration.
The general conception of a supercharged engine is of something very fierce. On the other hand, this Morgan will tick along on top gear, pulling steadily at 400 r.p.m., from which speed it will accelerate readily up to its maximum of a shade over 90 m.p.h., although fitted with its normal equipment of lamps, wings, windscreen, spare wheel, and so forth.

Henry Laird
The owner, Henry Laird, accompanied by Mrs. Laird,
climbing a difficult hill in a big "open". The tempo-
rary absence of a front number plate will be observed.

To all intents and purposes the supercharger has given the machine two distinct characters; first of all it is a slow, slogging, quiet "potter-bus." Then, given more throttle, it becomes capable of holding almost any fast car or solo motorcycle on the road! The "blower," of course, is in operation at all speeds, but the "familiar whine of the supercharger," so beloved of racing-story writers, is quite absent even when the Morgan is going flat out. Due, of course, to the low compression ratio starting is as easy as with the most amiable two-stroke.
Mr. Laird told us of a test which he carried out on Litton Slack - that notorious Derbyshire test hill. He says that the terrific power which the engine developed enabled the 1 in 4 slant to be tackled at 35 m.p.h., at which speed the hill seemed almost to flatten out, and the gradient became of no consequence whatever. Main road hills are simply child's play to the vehicle, and Mr. Laird claims that he has yet to find a normal hill that cannot be surmounted on top with ease.
Having read this account of hyper-super -performance the sceptic is liable to raise questions of reliability and running costs. We are informed that reliability remains unaffected; in fact, one might say that it has been improved by supercharging the engine. This is claimed to be due to the fact that the Morgan, when supercharged, runs at a much lower engine speed and has much smoother power production. So far as fuel consumption is concerned, at an average speed of 40-45 m.p.h., it is stated to be between 30 and 35 m.p.g. - a figure which can hardly be beaten by the average normal big twin of similar capacity.

Speed and Economy

Mr. Laird, as an example of the machine's capabilities, described a run which was recently taken to the Lake District. A distance of 98 miles was covered in 1 hour 55 minutes, during which distance only three gallons of petrol were consumed and one pint of oil was used for the engine and "blower."
A few weeks ago, on the occasion of the Cotswold Trial, a member of the staff of Motor Cycling had the opportunity of taking a trip in the passenger's seat of this amazing machine. Used as he is to performances which are definitely on the higher scale, he was immeasurably impressed by the turnout.
Let his own words convey these impressions: -
"Imagine yourself tootling along a gloriously straight stretch of highway at about 70 m.p.h. in a very rakish, trials-equipped Morgan. The man at the wheel turns to you and, in a most matter-of-fact way, says: "Would you like to go really quickly?" You nod an affirmative. He puts his foot down hard on the accelerator and instantly you get a kick in the back that amazes you with its suddenness and force.

VN 2810 Henry Lairds S.S. Morgan
(Right) A head-on view of the Morgan. The inconspicuousness of the "blower" is a noteworthy point.

Zoller Compressor
(Left) The Zoller compressor which wrought such a change in the character of Mr. Laird's Morgan. The flexible metallic tubing is the long induction pipe along which the compressor blows the mixture.

"If you want to experience the wonderful thrill of doing this, then try to get a ride with Henry Laird, in his supercharged Morgan, a description of which you have just been reading. I had a taste of it on the Sunday after the "Cotswold," and it was one of the best hour's motoring I have ever had.
"The machine would amble along in a most sedate and gentlemanly manner, but immediately the throttle was opened to any appreciable extent the outfit became the most wonderful mile-cater on three wheels that I have ever come across. Its acceleration was literally stupendous, both from low speeds and even when doing over 75 m.p.h.

Smooth Power

"Another feature which greatly impressed me was the smoothness of the power unit. It ran more like a four-cylinder job than a twin throughout its range. Even when accelerating sufficiently quickly for the rear tyre to leave a black mark on the road, no trace of harshness or snatch could be felt.
"With such a magnificent model to play with, I can well understand, the great enthusiasm Henry Laird and his wife have for our sport. Mrs. Laird, incidentally, accompanies her husband on all the trials in which he competes. Small wonder, too, that spectators on hills are always impatient for the arrival of this trio."
Enthusiasts will see in this Morgan something for which their hearts have yearned for years. Undoubtedly it is one of the most remarkable three-wheelers which have ever appeared on the road, and its success in the spheres in which it has been extensively used by Mr. Laird has proved that supercharging has possibilities probably undreamed of by the ordinary man.
Of course it must not be thought that supercharging is a cheap process. It cost quite a bit of money to "blow" the Morgan and much water will flow under the bridges before it is likely that machines with superchargers will be available at prices within the reach of everyone. Nevertheless, all motorcyclists who have any interest in the development of power output will read the foregoing with keen attention.

Remarks: The Super Aero of Henry Laird called "Red" has survived until today and is still being raced with great success by Larry Ayers in the USA. In our Photo Album No. 8 you will find some photos of "Red" taken during the race at Buttonwillow in May 2000. If you want to see "Red" in action check Events and Forum for Races in the U.S.A.

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