The 4.2-Litre V8 Sunbeam Tiger

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A Handsome Compact Anglo-American Sports Car with the Emphasis on Effortless Acceleration

The use of American vee-eight power units in British high-performance cars is an interesting development likely to increase—Bristol, Jensen, A.C. Cobra, and a number of big sports/racing cars of even more limited output use such engines. But whereas the emphasis has been either on luxury travel or competition performance of a hairy kind, the Sunbeam Tiger 260 conceived by the Chrysler-Rootes Group is a practical, road-going sports car. No combination of American vee-eight in a British chassis could be happier, for the snug installation of the “cooking” 141 (net) b.h.p., 4,261-c.c. push-rod-o.h.v. Ford V8 engine, coupled to a Borg-Warner gearbox, in the long-established and otherwise mainly unaltered Sunbeam Alpine transformed this somewhat harsh but fast and compact sports car into a very accelerative, extremely effortless motor car without in anyway changing its sporting characteristics.

Jensen Motors of West Bromwich did the structural modifications necessary to install the Ford engine into the confined underbonnet space and MOTOR SPORT commented on the new Sunbeam Tiger last April, when the Continental Correspondent drove a perfectly normal example over an electrically-timed s.s. 0.25-mile in 16.34 sec.

This gave a clear indication of the performance of the new hybrid, and D.S.J. was, in general, favourably impressed, as I was, especially when, going to Goodwood in the car, I found it possible to wuffle up South Harting hill in the 2.8-to-1 top gear and later enjoyed the smooth surge of acceleration on one of the quickest journeys I have made between the Sussex circuit and home.

We now present a full road-test report on this interesting and desirable Rootes Group sports car, discussing it in detail. It is virtually the former 4-cylinder Sunbeam Alpine re-engined, and is a pure 2-seater sports car with a seat behind the two front seats for the occasional doubled-up passenger, dog, or luggage, although there is a spacious boot for the last-named. Outwardly the car is recognisable as a Tiger only by the “Tiger 260” badges on sides and tail (the 260 represents the engine’s swept volume in cubic inches) and the “Tiger” scroll incorporated in the plated strip along the waistline, over which the “Sunbeam” lettering front and back takes precedence—it is not necessary to run the car exclusively on Esso. From the recognition aspect the discerning will also note the twin exhaust pipes. There are “Rootes Group Sunbeam” badges on the skies of the tail, and the old Talbot badge on the radiator grille, so this is a well be-badged car, but the badge’s are small and discreet. The key-ring carries the old Sunbeam-Talbot badge.

As one expects of Routes’ products, the interior of the Tiger is tastefully appointed. The driver’s and passenger’s seats are tight-fitting, separate, bucket-type seats, the backs adjustable in rather wide stages after side handles have been lifted and then pressed down to lock the seat-back in the desired position. The backs fold forward onto the cushions to give rather restricted access to the back compartment. In view of the short wheelbase the back axle intrudes into the cushion of this back shelf and the car is best regarded as purely a 2-seater. The steering column is adjustable after unlocking a large knob on top of the steering wheel and this, in conjunction with the adjustable seat, enables a comfortable driving position to be selected, with choice of “Caracciola” or “Farina” stance. It is also possible to adjust the small, polished-wood-rimmed spring-spoke wheel so that it is low enough not to obstruct the forward view. The wheel carries a full horn-ring, sounding a powerful horn.

Visibility is good, over a plain bonnet, although the screen pillars are somewhat thick. The gearbox tunnel is as wide as formerly, so that the pedals are very slightly biased to the o/s, but there is room for the clutch foot, resting on the lamps’ dipping button, beside the clutch pedal. Clutch and brake pedals are of pendant-type, the accelerator a treadle.

Between the front seats is a very useful, lockable stowage-box with padded lid, which endeared itself to me because it accepted a Rolleiflex camera and lightmeter. Just ahead of this there is a lidded ash-tray, on the transmission tunnel, and immediately in front of this rises the well-placed gear-lever, with gaitered base. The floor is thickly carpeted, with a rubbing-mat for the driver’s feet; it was hanging loose above the accelerator pedal.

The instruments are spaced out along a facia of polished walnut veneer, well crash-padded above and below. Before the driver are the 140-m.p.h. speedometer with total and trip odometers and the tachometer reading to 6,000 r.p.m., with the red-section from 4,700 r.p.m. Between these is the oil-gauge. These are British Jaeger instruments, very clearly calibrated, the speedo-meter reading in k.p.h. as well as in m.p.h. and the needles moving in complementary arcs. To the left of the tachometer there is a Lucas ammeter and on the centre of the panel are located the Jaeger fuel and water temperature gauges, also fully calibrated, the former in litres as well as gallons, the latter in deg. C. and deg. F., with a not-completely-dependable Smiths clock (which is an extra) between them. Above these three small dials the twin heating and ventilating horizontal controls quadrants are neatly located. Warning lamps and the flick-switches for lamps, panel lighting and the two Lumax fog-lamps, fitted to the test car, are scattered, but the wipers and adjacent washers button are conveniently positioned for the fingers of the right hand, as is the flick-switch for the heater blower. The log-lamp switches are on a little panel of their own, below the facia, and rather obstructive in a crash. On the left-hand side of the facia there is a large open cubby-hole, with a map-lamp which has its own switch, above it. There is a choke label but, as the Ford engine has an automatic choke, the hole is blanked off.

Not every sports car has anti-dazzle vizors, but these, of soft padded type, are provided on the Sunbeam Tiger, although there is no vanity mirror, and, although detachable, the vizors do not swivel. Below the facia on the test car the excellent push-button Radiomobile radio and speaker were fitted.

On the left of the steering column a slender stalk looks after the turn-indicators and daylight lamps-flashing. The band-brake lever lies well out of the way, horizontally on the right of the driver’s seat, where it is immediately to hand, but savages the knuckles if it happens to be in the “on” position while the driver’s large window winder is being operated. These winders need five turns to lower fully the window glasses. The very wide doors, with good “keeps,” provide for easy entry and exit and have push-button external handles, simple metal “pulls” and lever-type inside handles which lift up to open the doors. The luggage-boot lid has external plated hinges and the efficient quick-action fuel tiller is recessed in the o/s of the body. The bumper over-riders are rubber capped in the modern style, and the appearance is embellished by wheel trims, through which the tyre valves protrude, and whitewall Dunlops.

The bonnet panel has to be propped open. The boot has a slam-type lock, but does not require the use of the key to open it unless purposely locked. The boot is shallow but long, and should take all the luggage the occupants of a car of this type normally take with them. The spare wheel lives horizontally under the floor, with the 12 volt 67 amp./hour battery beside it, the lid of the latter intruding only slightly into the luggage compartment. The test car was equipped with Irvin-Routes Safety-belts.

Naturally, modifications were necessary to the front-end of the Alpine to enable the Ford V8 engine to be installed, this engine being a fine example of modern thinwall iron-casting techniques, so that, while developing a gross b.h.p. of 164, and 258 lb. ft. torque at only 2,200 r.p.m., it is of notably low weight. This engine retains its Carter 2-barrel carburetter, and, having a c.r. of 8.8 to 1, will consume premium fuels. A new cross-flow radiator is used, filet is fed electrically, and there are two entirely separate exhaust systems, each with its own silencer and plated tail-pipe. Petrol is contained in two tanks, one in each back wing, but they feed as one, giving a capacity of 11.25 gallons.

The transmission is entirely new, a hydraulically-operated clutch conveying the drive to a 4-speed all-syncrornesh Borg-Warner gearbox, while a heavy-duty propeller shaft drives a high-performance Salisbury hypoid back axle with the satisfyingly high ratio of 2.88 to 1. To cope with the extra weight of the engine the Alpine i.f.s. has higher-rate coil-springs and the damper settings have been changed. The front disc/rear drum servo-assisted braking system is unchanged but a modified front cross-member carries a new rack-and-pinion steering unit.

On the road this Sunbeam Tiger handles and responds like a typical sports car, and possesses that lineflow of smooth power that is associated with a big-capacity multi-cylinder vee power unit, acceleration producing scarcely any sound other than the characteristic note from the exhausts. The Tiger’s most impressive feature is its excellent, effortless acceleration, even from very low speeds in top gear. The accompanying table quotes the figures for standing-start pick-up, but only driving experience of the Sunbeam-Powered-By-Ford can convey how enjoyable this smooth flow of power makes the car on the road, and how rapidly the Tiger disposes of traffic tangles. The rear-view mirror, incidentally, is of the dangerous ‘ diminishing ” type, quite unnecessary with acceleration of this kind!

Some idea of the potency of this Sunbeam-Ford’s pick-up in top gear can be conveyed by quoting further acceleration times – 30-50 m.p.h. occupies 5.5 sec., 60-80 m.p.h. only 8 sec. It will pull from 12 m.p.h. (500 r.p.m.) in top gear. The s.s. 0.25-mile time was not quite so good as that obtained by D.S.J. in another Tiger but he was alone in the car, whereas we timed the car two-up, with a fairly full tank of Petrol—many runs of 17 sec. were made without exceeding 4,700 r.p.m. At this speed the genuine maxima in the gears are, respectively, 42, 66 and 87 m.p.h. Taking the engine 300 r.p.m. “into the red” gives an impressive 90+ in 3rd gear.

On good roads the handling is excellent, although care has to be taken to get the car straight before opening the throttle in the lower gears on a slippery surface! Normally it is usual to roll away in 2nd gear and go straight into top; the acceleration Still being entirely adequate for most situations. The gear-lever has a large knob labelled with the gear positions and a neat lift-up catch in prevent reverse being selected inadvertently. It is a “mechanical,” notchy change, heavily spring-loaded towards the high-gear positions, but with good syncromesh on all four forward speeds. Third gear is commendably quiet, but there is slight 1st and 2nd gear howl and back-axle whine. The clutch has a rather long travel, is not too heavy for a sports car, and is moderately smooth. Both front wings are in full view of an average-height driver.

The steering is light, once on the move, accurate, perhaps a bit “dead,” with gentle castor-return action. It is usefully “quick” steering, geared 3.5 turns, lock-to-lock, with no lost motion. A great deal of fierce kick-back is transmitted through the wheel, which is shiny and slippery but has token finger grips. As the suspension, being stiff enough to kill all noticeable roll except where direction is changed very suddenly as the car is being furiously accelerated, gives a rough, rattly ride on bad roads, the Sunbeam Tiger is a sports car somewhat in the vintage image. Even on good roads the ride is lively arid, in spite of stiff springs, the nose dips under heavy braking, deflecting the headlamp beams. The front-end becomes squidgy under these conditions. There is not overpronounced understeer, the normal cornering trend being pleasantly neutral. I am told that the suspension is impossible on European back routes, but it is quite acceptable in Britain, especially as the snug-fitting driving seat, if unyielding, is quite comfortable on long runs, while passengers praised the comfort of their seat. Elbow room for the driver’s right arm is restricted. The steering lock is restricted also, particularly to the right, resulting in a turning circle of 36.5 ft.

The back axle, on half-elliptic leaf-springs without any other location, can be made to tramp furiously if too-fierce bottom-gear take-off is indulged in, and the Dunlop RS5 nylon tyres can be made to spin relatively easily. The brakes are light to apply and adequate, but for prolonged mountain driving it is possible that something larger than the 9.85 in. discs and 9-in, drums might be an improvement. It is possible that a larger tyre size than 5.90 x 13 might also be desirable for really hard motoring, but only the most spirited cornering provokes protest from these RS5s. The speedometer was virtually accurate when checked at 50 and 60 m.p.h.

Taken all round, this mating of American vee-eight engine and popular British sports car has very definitely succeeded. The Sunbeam Tiger is fascinating to drive and offers really good and usable performance for a total outlay of £1,445 10s. 5d., particularly as no skimping has been indulged in to gain a few more m.p.h. or greater acceleration, the Tiger weighing, with its very adequate equipment and finish, over 22 cwt. The weather protection is excellent, and the hood, although tedious to stow in its metal rear locker, does not drum and looks durable. Its rear quarters do constitute a blind-spot in certain situations, however. The glass door-windows do not create much draught when open; the quarter-lights are fixed. A hard-top is available for an extra £60 8s. 4d.„ inclusive of tax.

The headlamp beam is rather cut off when dipped and the full-beam: warning light is dazzling. There is bright and dim panel lighting but neither this, nor the map-light, illuminates the heater controls.

The Sunbeam Tiger will poodle along at 15 m.p.h. in its high top gear or accelerate splendidly to a maximum of 116 m.p.h., and it cruises effortlessly at any speed up to maximum. At 90 m.p.h. on the Motorways the engine is turning over at less than 4,000 r.p.m. and oil-pressure is normally 50 lb./sq. in. Water temperature is rather high, at 85″ C., but I never made the radiator boil. As to petrol consumption, pottering around, enjoying the easy top-gear performance, I got 19.2 m.p.g., and on a fast main road drive, speed restricted only by the appalling traffic hold-ups on the notorious A31 Winchester-Bournemouth road, the figure improved to 22.0 m.p.g., so it should normally be possible to obtain better than 20 m.p.g.

A full tank of petrol lasted 203 miles, but consumption would have been increased by the recording of acceleration figures, and something like 225 miles should normally be possible. The electric pump primes an empty tank efficiently. After 700 miles no oil had been used. To inspect the impressive machinery the bonnet top has to be lifted and propped up. The long dip-stick is accessible, in a tunnel behind the alternator.

To sum up, the Sunbeam Tiger V8 is a most entertaining sports car, and one possessing performance which makes it a very fast car indeed in terms of average speeds and, in the right hands, a very safe one. Its engine should be extremely durable, being so lightly-stressed, and it provides the fluid power output and ” there-and-gone ” acceleration I encountered first in the side-valve 3.6-litre Ford V8 some years before the war. At its selling price of less than £1,500 this well-finished, sensibly equipped Rootes Group product, in something of the vintage tradition remembering the steering kick-back and hard suspension and respectably high power/weight ratio, is indeed an excellent addition to the ranks of British sports cars. Most of the minor shortcomings referred to above have been inherited from the Alpine and may well be designed out as the Tiger is developed further, but had the Alpine not been used as a basis the price would presumably have been far higher. While an engineer might raise an eyebrow at some of the installation details and the Sunbeam Tiger, like the Daimler SP250, has a better engine than chassis, taken all round it is an excellent investment, admirably suited to modern traffic conditions.—W. B.

The Sunbeam Tiger 260
Engine: Eight cylinders in 90″ vee formation, 96.5 x 73 mm. (4,261 c.c.). Push-rod-operated overhead valves. 8.8-to-1 compression-ratio. 141 (net) b.h.p. at 4,400 r.p.m
Gear Ratios: First, 6.8 to 1; 2nd, 4.86 to 1; 3rd, 3.71 to 1; top 2.88 to 1.
Tyres: 5.90 x 13 Dunlop RS5 on bolt-on steel disc wheels.
Weight: 1 ton 1 cwt. 1 qtr. 27 lb (dry weight)
Steering Ratio: 3.167 turns, lock-to-lock
Fuel capacity: 11.25 gallons (Range approx 225 miles.)
Wheelbase: 7 ft 2 in
Track: Front, 4 ft. 4 in; rear, 4 ft 0.75 in
Dimensions: 13 ft 0 in x 5 ft. 0.5 in x 4 ft. 3.5 in (high – hood up)
Price: £1,195 (£1,445 10s. 5d inclusive of purchase tax).
Makers: Sunbeam-Talbot Ltd., Ryton-on-Dunsmore, Coventry, England