To many drivers of long experience there is a particular charm about the type of car which includes in its specification a sizeable engine pulling a high gear; that is, having a low final drive ratio. The attraction of such a car lies in its ability to give high cruising speeds at cornparatively low engine r.p.m., with the result that the level of mechanical noise is low and a really fast gait nevertheless appears to be unhurried. There have been a number of such cars in the past, such as the 30-98 Vauxhall, to mention only one famous name which will instantly come into the minds of those whose experience goes back far enough, but there are few modern examples. The Jensen Interceptor, however, does definitely possess that big-engine, high-gear charm of the past, but offers it in modern guise with the degree of smooth operation that a well-designed six-cylinder engine can give when it is running comfortably within its speed capacity. Moreover, the very satisfying performance of the power unit is accompanied by modern standards of road behaviour in such important matters as suspension, steering and braking.
   In appearance the Interceptor is modern to a degree, with a full-width frontal aspect distinguished by a more or less oval-shaped radiator grille set low down so that the faired-in head lamps are actually above it. The wings are of helmet section, showing a definite line along the top, and they run straight along the bonnet and door sides into the rear wings, which merge with the well-rounded tail. The lines of the car are, in fact, clear cut and decidedly graceful, attracting considerable admiration, as was evidenced during The Autocar test in this country and on the Continent. The bonnet top is a single panel hinged to the scuttle at the rear and having the customary type of front locking device operated from a control beneath the scuttle; a safety catch which should be infallible is a part of the locking device.
   The body is a close-coupled four/five-scater two-door cabriolet, the wide doors being hinged on their forward edges and carrying drop windows and ventilating panels. The screen is a fixed flat panel set at an appreciable rake and the section of the metal pillars provides adequate strength in this important component of a convertible body but at the same time does not obstruct vision unduly.
   Driving vision is, indeed, unusually good for such a sizeable car; it is helped by the downward slope of the bonnet top, which is louvred at its front edge to admit air. The driver can see the crown of the left wing, and is thus easily able to judge his clearances in traffic. Rearward visibility is also unusually good by virtue of the transparent bottom section of the folding head (top), which extends the full widthof the rear scat; this was found to simplify manoevring not a little in, for instance, the confined space of the train deck of the Dunkirk ferry. The head is easily lowered or raised by one pair of hands, and when down is neatly encased.
   In.view of the car's expected speed capabilities it was arranged to take it to the Jabbeke road in Belgium, for the magic three figures were expected and were, in fact, attained. The highest car speedometer reading shown was 102 m.p.h., and the accuracy of the instrument was tested by numerous stop-watch readings over kilometre distances as well as by the fifth wheel electric speedometer. The two series of calibration tests showed that at the lower end of the scale there was a discrepancy but that this rapidly became less important, the car's instrument being 1 m.p.h. fast at 30 m.p.h. and remaining only 1 m.p.h. fast up to 80 m.ph., when it became more nearly accurate as the 90 and 106 marks were approached, by reason of the increase in tyre diameter at high speeds owing to centrifugal force.
   At 102 m.p.h. the engine speed as shown by the rev counter mounted in front of the driver was about 4,200 r.p.m., and the engine remained smooth although it begins to become progressively less happy if pushed up to 4,500 r.p.m., as it can be on the indirect ratios. On the smooth concrete surface of the Jabbeke road the Interceptor was perfectly steady and comfortable at its maximum, which was held for perhaps a couple of miles, and the steering wheel could be released. A strong cross-wind was blowing, but the car was virtually unaffected by it, only the strongest gusts being perceptible through the steering. Satisfying as such a maximum may be to the enthusiast, the high cruising speed and vivid acceleration which the 4-litre overhead-valve engine gives are more important in long-distance Continental touring, for which the car is obviously designed. Naturally, the acceleration on the indirect ratios is the more impressive, but despite the 3.28 to 1 top gear the car's ability to respond to the throttle without a downward change is of a high order. As maximum torque is given at 2,200 r.p.m., which corresponds to a topgear road speed of just over 50 m.p.h., the liveliness of the car is greatest just when it is most likely to be required.
   One can, therefore, drive the Interceptor fast in two ways, either making use of third gear so as to obtain the most rapid acceleration after dropping from cruising speed to, say, 40 m.p.h. or remaining on top and being content with a slower - but still speedy - return to cruising speed. Moreover, one may do this on the level or on a hill, for the reserve of power is such that the car possesses a flexibility quite remarkable in view of the low final drive ratio.
   Cruising speed may be anything the driver desires and the road allows up to, say, 80 or even 85, m.p.h. for the r.p.m. at 85 m.p.h. are about 3,500 and the engine is running smoothly and below its peak power. An average speed in the fifties is attained without the driver or passengers realizing it, and without any conscious effort on the part of the driver. Distances of 50, 51, 56 and 55 miles were actually covered during the test run on Continental routes in four consecutive hours, which included two stops of five minutes each, for a level crossing and for petrol, and traversing sundry villages and towns at a reasonable gait. These hourly distances are understandable on Continental roads, for when 13 miles can be covered in 10 minutes, as was done, the time lost in a town is quickly made up.
   Another attraction of a low final-drive ratio is its beneficial effect on fuel consumption. If the car be driven without too frequent recourse to the lower gears it will cover 24 miles to the gallon while maintaining a 50-plus average speed. On the other hand, this will fall to 20 m.p.g. if the indirect ratios are in frequent use, this being very noticeable when acceleration figures were being obtained.
   High average speeds demand much more than lively acceleration, of course. The brakes must be efficient and dependable, the steering must be precise and accurate, and the suspension must not only be comfortable but also must give good road holding. The Interceptor has Girling full hydraulic brakes and although the linkage is such that rather more than usual pedal pressure is called for theresults leave nothing to be desired. However hard the brakes are applied there is no suspicion of grabbing, nor does the car deviate from its path. In this connection it should be mentioned that the small grilles which flank the radiator grille are to allow the air stream to flow round the front drums. Certainly no brake fade was experienced, despite repeated stops from high speed while performance figures were being obtained.
   The steering is reasonably high geared, which allows the driver to manoeuvre quickly on winding roads, and is commendably light. The car understeers slightly, and never oversteers, so that one can hold it into a bend with confidence. Also the steering is accurate, free from any feeling of sponginess, and not sensitive to road inequalities.
   Front suspension is by wishbones and coil springs. Although it is so "soft" that the front of the car can be bounced by pulling the bumper up and down, it does not feel too soft when the car is in motion, and there is no pitching. The ride is level and comfortable, with an absence of road shocks. The rear half-elliptics also give a soft ride, but only on really bad surfaces at speed do they give the impression that slightly more control action would be an improvement. On reasonable road surfaces both the comfort and the road holding are in keeping with the car's capabilities.
   The driving position in the Interceptor inspires confidence at once. The front seat is of bench type, and is wide enough to scat three normal adults unencumbered by heavy coats, but the lateral steadiness of the car, even when taking open bends at speed, is such that neither driver nor passenger tends to be thrown out of place. The scat is adjustable, so that the driver can assume the position he favours, the large diameter wheel is at a comfortable angle which does not cause arm strain, and there is plenty of room for his left foot alongside the clutch pedal. The pedals are well spaced also. The central gear lever is commendably rigid and gives precise control, although the detent springs call for a little effort to overcome them when engaging first or second gear from rest. The actual changes are easy, and the gear box is quiet in operation, especially on third.
   Instruments are well grouped in a leather-covered facia, which is non-reflecting; speedometer and rev counter are easily seen by the driver. A panel light switch is matched by one for the screenwipers. A switch under the driver's control operates a map light beneath the scuttle. Three control levers project from beneath the large central horn button, the top one controlling the Trafficators, and the other two being for manual ignition control - not recommended but available if required - and for a spot light if specified. Dipping is by a foot switch located to the side of the clutch pedal.
   The rear seat is intended for occasional use and the legroom is somewhat restricted. although adequate for a single occupant, who can sit at a slight angle. Access to the rear seat is by tipping forward the divided back rest of the front scat, each half being pivoted so,that it moves forward at an angle, giving a wide opening between its edge and the door.
   Engine accessibility is good, the sparking plugs, distributor, coil and dipstick from the right side, and the carburettor and air cleaner from the left side. Also on the left side is an electrical connector socket for the immersion heater built into the lower water connection between radiator and cylinder jacket, so that it can be coupled to the domestic electric supply in winter. Jacking sockets are adjacent to each wheel. Accommodation for luggage in the tail locker is considerable, although the locker also houses the spare wheel and tools. Useful pockets are provided at the bottom of the doors, at the back of the front seat, and at the left of the scuttle. The glove box in the facia has a lock, and the tail locker also has locks in its two handles. Locker lid and bonnet top have automatic supporting stays.
   The Interceptor is well equipped, and has a heater and demister installation, also an inspection lamp and connection socket, in addition to the fittings already mentioned. It is, in short, a touring car of refinement, smooth and quiet in operation, but with the performance of a sports car. It was notable that even on Belgian and French pavi there was no serious body or chassis noise, nothing more than a slight chatter of a partly open window glass in its channels.
   (Roadtest 1953)
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