A Sturdy American Two-tonner on Test
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Road Test No. 59.
IN the commercial-motor industry the two names of Studebaker and Pierce-Arrow are very well known. During the past few months the product of these two American concerns, the Studebaker PierceArrow, has made its way on to the British market ; it is handled in this country and in Northern Ireland by Henlys, Ltd., Henly House, 385-387, Euston Road, London, N.W.1. This concern, of course, has considerable facilities for the distribution and servicing of vehicles ; it holds numerous agencies and concessions in the private-car market, but is pinning its faith to the Studebaker Pierce-Arrow in the commercialvehicle field.
The model which we took over for testing was a brand-new 2-tonner with drop-side lorry body. The chassis in question has a wheelbase of 13 ft. 4 ins.; a type 1 ft. shorter in this dimension is also supplied. The model we tested is priced at £340 in chassis form, whilst the shorter machine is listed at £315.
At the start of our trial the speedometer recorded 188 miles; while the machine was in our hands it covered over 100 miles, and at the end was pulling appreciably better c36 than at the beginning. The fuel consumption also was improving. On the weighbridge the gross figure was 4 tons 8* cwt., the weight consisting of 80 56-lb. weights, so that the exactness of the pay-load was definite.
Shaping our course northward, our first endeavour was to get away from the London traffic before carrying out any specific test. During the first few miles the impression was formed that the vehicle was somewhat unusual in that the Handy governor on the induction pipe limited the all-out speed to
little short ,of 40 m.p.h. This is rather a high figure for a machine having a governed engine, but there is a great deal to be said for the system, because it allows a performance as good as any operator may reasonably require, but prevents the vehicle being 'flogged " mercilessly, as is so often the lot of machines in the 30-cwt. or 2-ton categories. The maximum speeds in the various gears are: First; 5 m.p.h.; second, 15 m.p.h.; third, 27 m.p.h.; top, 39 m.p.h. The lowest speed on top gear was 6 m.p.h.
The most prominent noise was a whistle from the air cleaner at one particular throttle opening. The indirect gears were reasonably quiet, and the engine was commendably silent. The spiral-bevel rear axle was free from hum, both on the run and on the overrun; a portion of the credit for this state of affairs, no doubt, belongs to the straddle mounting for the bevelpinion shaft.
Our chief criticism concerns the disposition of the pedals. The system on the vehicle tried consisted of the following lay-out, from left to right : Clutch, accelerator, brake, headlamp dipper. The accelerator pedal is placed low down between the shanks of the clutch and brake pedals ; depression of the clutch pedal while the right foot rests upon the accelerator may cause the right boot to be trapped, with a consequent racing of the engine.
Tha dipper pedal, which, incidentally, gives an extremely useful lighting control, necessitates removal of the foot from the accelerator, which, on a long up grade, is best avoided. It would be advisable, in our opinion, to rearrange the pedals in the following manner, from left to right :—Dipper, clutch„ brake, accelerator.
Powerful Brakes.
For the braking trials, the pedalcontrolled four-wheel set was used. This is of the self-energizing type, and the shoes come into action very rapidly, but without a tendency to cause skidding. Although our trials were executed on a dry road, we tested, at other points during the trial, fierce brake applications on sticky surfaces. It was possible to lock the wheels, but the vehicle always maintained a forward direction—skidding could not be occasioned unless the steering wheel was handled in a provocative manner. The brake lever operates the shoes in the rear-wheel drums. It requires a fair amount of force to bring it into action.
With regard -to acceleration, the graphs speak for themselves. The performance, generally, was good ; the gear ratios are sufficiently widely separated to allow use of the vehicle over really bad ground, as the first-speed ratio is 37.33 to 1.
As regards hill-climbing, we found it best to change down to a lower ratio while the engine was revving fairly quickly. At 25 m.p.h. on top gear (5.83 to 1), long, gradual rises can be surmounted with power in hand, but when the speed falls to 23 m.p.h. a change to third gear is well repaid. Normally, there is no need for first speed, unless the machine be starting on a hill.
An Emergency Gear.
The first-speed ratio is sufficiently, low to permit a very easy get-away on 1 in 6, and the clutch can be manipulated so that on steeper gradients the engine can take up its work without snatch. Should the gradient ease slightly, rapidity of the gear change allows the ratio to he altered with the minimum loss of way. During our trial the weather was cold and foggy, so that most vehicles had engines running at low temperatures. That of the Studebaker Pierce-Arrow maintained a normal running temperature varying between 118 degrees and 132 degrees
F. Prolonged use of the lower gears caused very little rise of the thermometer.
A useful feature is a dashboard indicator for the temperature of the water in the cylinder head. It is calibrated in degrees ; it shows when the water has attained a normal running temperature or when it is nearing the danger mark. Its action was consistent and it should prove a useful guide when working under arduous Conditions.
On this model the dashboard equipment is complete, and the steering wheel is absolutely clean except for the horn button in its centre. Automatic ignition advance is employed, but a small hand control is provided on the facia board. This is useful for starting-up purposes, otherwise it is not used. If it be desired temporarily to increase the engine idling speed this can be done by means of another control on the dash. Throughout th the trial the standard setting of e Stromberg pump-type carburetter remained untouched. For the fuel-consumption test a two-gallon tank was rigged up and the connected to float chamber of the carburetter, the pipe from the camshaft-driven pump being discon-nected, as was the feed pipe from the main tank to the pump. On the two gallons of spirit the vehicle ran 25.9 miles, which gives a return of 12.95 m.p.g. for the total distance; .7 mile was covered in third gear, .1 mile in second gear and .05 mile in first gear, giving a total of .85 mile on the indirect speeds. The 25.9 miles were covered in 59 minutes, and the vehicle was driven as it would be by most commercial-vehicle drivers—as fast as circumstances allowed, using the maximum speed on about four occasions throughout the total distance. _Considering the average speed, the consumption was by no means heavy for a machine having a six cyfindered engine of fairly large capacity in relation to the load carried. On the vehicle tested a metal cab was used, and this gave a commendable degree of comfort and silence. The only sounds audible in the cab were the hiss from the air intake and the occasional rumble from. the propeller-shaft universal joints when the vehicle was over-running the engine. Good Suspension. On the chassis we tested the springing system was perfectly standard ; if desired it is possible to obtain auxiliary springs above the main ones on the rear axle. This should be helpful for machines used for strenuous work. The standard system gives a creditable degree of stability coupled with comfort, and the length of the springs and their strength appear to have been well chosen in relation to the 13-ft. 4-in. wheelbase of the machine we tried. There was no pitching, and when braking hard over uneven surfaces there was little tendency for the wheels to spin and grip alternately owing to the tyres losing contact with the road surface,