THE Hudson Terraplane and the Railton Terraplane, which is the sports car developed from it, have in the past two years become words to conjure with when the subject of acceleration came up for discussion, and it was with great interest that we carried out a road-test on one of the latest ” Railtons.” Until we tried the car we had felt a certain doubt that such a light chassis could provide the feeling of stiffness and security one expects in an English sports car, but after half-an-hour at the wheel we satisfied ourselves that the unlikely had become the actual. A purposeful 80 m.p.h. along a bye-pass, and an easily achieved seventy on the short stretches of straight road which offered themselves on the course of the route taken added to the conviction that here was a thoroughbred sports car.
The winding nature of the main road taken soon gave opportunities of testing the cornering, which was found to be outstandingly good. The Goodyear Airwheel tyres seemed to lock the car to the road, and when brutal cornering caused slight squeal to come from the rear, the car still held steadily to its course, or if required the tail could be slid round by locking over the wheel or holding on the power in the most controllable way. There was no sign of plunging, twisting or any other vices often found with light chassis, and we acquire renewed respect for the stiffening effect of the steel sheet which acts as floorboard, and locks together the whole frame structure as far forward as the dash. The only disadvantage of its light weight was that over hidden culverts the back wheels were apt to be thrown off more than with a heavier car ; fortunately such obstacles are rarely met with. Though the suspension was so firm at speed, it was not harsh at low speeds, and the only time the Andre Telecontrols needed altering was when passing at speed over some badly corrugated stretches of road. A surface of this type is apt to
jar the wrists when taken at speed on the average sports car, but on the Railton the independent front springing seems to prevent the snatch from reaching the
steering mechanism. The steering is completely positive, and reasonably highgeared, and the car holds a steady course at speed even though there is little .caster action. The acceleration of the car has a character all its own, and when the pedal is put down either on top gear or second, the driver does ont receive a
push in the back,” but the whole outfit is wafted forward in effortless fashion, and getting away from a corner or overtaking other cars is a particularly satisfying manceuvre.
Tested over a cross-country journey frequently accomplished during the course of the season, and one which is always rather tiresome in the ordinary way, the Railton seemed to straighten out the crooked bits and flatten out the hills. and allowed the driver to put up an average which one could consider first-class on normal Main roads.
Even so, one hardly realised until a stop-watch had been used how fine the acceleration really is ; up to 80 m.p.h. its performance surpasses that of any unsupercharged car we have previously tested. It was not found possible to time the car on the track, but on runs in opposite directions On a main road the maximum speed readings on an accurate speedometer were 89 and 94 -m.p.h., which fully substantiates the claim of the makers that this is a 90 m.p.h. car. These figures were put up with the screen folded down and the air cleaner removed ; with these in position, 85 m.p.h. seems the maximum on the level.
The car tested was litte.d with a high compression head giving a compression ratio of 7 to 1. Pratt’s Ethyl was used and there was no sign of pinking, in fact the engine was remarkably smooth. The head scarcely affects the all-out speed, but naturally improves acceleration. Petrol consumption at fast touring speeds is 16 m.p.g., dropping to about 12 m.p.g, when the car is driven flat out on all :gears.
The brakes were powerful but came on progressively. Unfortunately the rear ones took effect in advance of the front set and locked the back wheels it the pedal was firmly depressed, but in spite of this we were able to pull up in the excellent distance of 50 feet from 40 m.p.h. Eighty miles an hour may be maintained indefinitely, and with the engine turned over effortlessly at 4,000 r.p.m., some astonishing averages may be put up. After some forty miles of this the engine showed no signs of tiring, and the owner informed us that he habitually kept his car at this mark on deserted roads. Owing to the light weight of the car, gearchanging is seldom necessary, but the gearbox is there to be used when required, and gives a useful 60 m.p.h. on second gear and just under 40 on bottom, with an engine speed of 4,500 r.p.m., while if required it may be taken up to 5,000 r.p.m. for short periods. There is no trace of period and the carburetion is clean through the range. Second gear runs quietly up to 3,500 r.p.m., but above that makes a high-pitched whine, which blends with the roar of air into the carburetter. Oil top gear, strangely enough’, this “power-roar ” is not experienced, while the exhaust is virtually inaudible
whatever the speed. The gear-change is a straightforward and. very fast one, but one would have prefetred a shorter and stiffer gear-lever. The other controls are well arranged. The steer ing wheel comes comfortably into the lap, the clutch, foot-brake and accelerator are at the right angle and the wind screen affords good protection, and in spite of the large bonnet one can see the whole of the off-side and the top of the near-side wing. The seat-back was specially arranged to be almost vertical on this car and gave an alert driving position, The lay-out of
rev. counter and speedometer was commendably neat, but one would have liked an oil, gauge and an ammeter in place of the safety lights which are the only indication that the lubrication and the lighting are working properly. When trying the Railton for the first time one is a. little apt to be led away by its acceleration and general liveliness from considering it as an everyday fast touring car, but these very qalities are just the Ones which make for effortless journeys at high speed. Returning to London we managed to restrain ourselves somewhat, and were charmed in turn with the way in which 65-70 m.p.h. could be kept up at moderate engine speed and with but a touch of throttle, while it was possible to glide without a sound through the towns along the route at 40 miles an hour with the full approval
of the local constabulary. After a hard day’s motoring the driver feels no trace of fatigue even in the wrists, which usually suffer most in fast driving, and this is no doubt due to the good weight-distribution and to the fact that one is driving a car weighing half a ton less than many of its contemporaries of similar wheelbase. Many prospective owners will ask” How will a light car such as this stand up to continued spells of hard driving ? The car tested had covered 7,000 miles of really hard work, scores of racing starts, ascents of the Brooklands test hill trials, and the week before had made second fastest sports car time at Brighton. The engine, chassis, and transmission seemed in absolutely new condition, and
there seems therefore no fear that the Terraplane will not stand up to the strain.
The eight-cylinder engine has a capacity of 4,168 c.c., gives 113 h.p. at 3,800 r.p.m., and is carried on rubber mountings at three points. Side-by-side valves are used, and a single down-draught carburetter, which is fitted with an automatic choke control, supplies the mixture. The carburetter is fitted with a large air-cleaner, and the fuel is pumped from the 13-gallon rear tank by an enginedriven pump. Coil ignition is used, with a spare unit in case of failure ; the distributor is accessible at the side of the engine, and 14 mm. sparking plugs are standard. The high-compression head costs an extra £7. The five-bearing crankshaft has balance weights and Lanchester damper, steel
connecting rods and alloy pistons are used, and the oil is cooled by passing through ducts on the side of the crank case. The sump holds I gallons. The honeycomb radiator is a handsome design and, equally important, holds 5 gallons of water.
The clutch is a single-plate unit with cork insets and runs in oil. The gearbox has a constant-mesh second gear, and the final drive is through an open propellor shaft with two needle-bearing universal joints to a spiral-bevel back axle. The chassis is a light but strongly-made structure with a large X-bracing behind the gearbox. It owes its special rigidity to the use of a steel floorboard which comes right up to the engine, locking the whole of the entire rear half of the chassis in one
rigid unit. The steel dash and other reinforcements not seen also contribute to its stiffness, so that the chassis weight is about 2 cwts. heavier than that of the early Essex Terraplaries. Long half-elliptic springs are used all round, but the front wheels are independently sprung. The centre part of the front axle consists of two parallel links joined by short links which carry the axle ends, to Which the springs are also attached. Either of the outer halves of the axle can therefore swing up in company with the central links without affecting the op
posite end. Andre telecontrol shock absorbers are fitted to the back and front axles in addition to the standard hydraulic plunger type.
The wire wheels carry 16 by 6.25 Air Wheel tyres running at 25 lbs. pressure, which help to insulate the chassis from road shocks without causing instability. Cable operated Bendix brakes are used. The car tested was fitted with a light and
body by John Charles. In spite of its light construction there was plenty of room, and the front seats, without being luxurious, gave adequate support. There is plenty of leg-room in the back, as deep wells are provided. The passengers sit rather high over the back axle, but the body sides are carried up to give them protection.
We are indebted to Mr. Robert Strang, of Messrs. Shaw & Kilburn, 117, Great Portland Street, W. 1, for the loan of his private car for this interesting road test. Messrs. Shaw & Kilburn carry out all the speed tuning on the Railton cars, and as this is carried out without altering any of the standard components, one can rely on having the performance outlined above on all the Railton cars produced.