Road Test 1967 Jensen Interceptor

Road Test 1967 Jensen Interceptor – International splendour, superb engine and transmission, tremendous performance, comfortable armchair seats, very well-balanced handling, brakes judder when hot, over-complicated heating and ventilation. Power slides are easy to provoke and even easier to control. This we confirmed on the snow-bound private roads of Luton Hoo’s magnificent grounds.

If you can’t beat them, employ them. Jensen first obeyed this basic industrial law of survival when they discarded the 4-litre Austin DS7 engine that powered their elegant Jensen 541R and dropped 5.9-litre (later a 6.3-litre) Chrysler pack into their inelegant Jensen C-V8 replacement. Then they had brutal performance and impressive mechanical refinement but styling that barred them from the corps d’elite dominated by the Italians. So Jensen went shopping again to Superleggerra Touring’s establishment in Milan — and bought a new set of clothes (steel ones, this time, not glass fibre) which were displayed at last 1967 October’s Motor Show on a Jensen C-V8 chassis renamed the Interceptor, reviving an earlier Jensen label.

The Americans must take credit for the superb engine and transmission and the Italians for the stunning body but it is Jensen who are responsible for combining the two with some sound British engineering into one extravagant package that lifts the Interceptor no the top bracket of our desirable property list. The accompanying litres show what a tremendous performance this latest Jensen has but they do not really convey the absurd ease with which 325bhp trusts the big car up to 140mph, nor the imperceptible pause as one gear slips into another in the uncannily smooth automatic gearbox. Passengers are remotely isolated from the internal turmoil of the big V-8 and the hubbub outside, though wind noise becomes prominent above 80mph.

{gallery}Jensen-Interceptor{/gallery}

It is a bit unkind to call the Jensen a 2+2 because the rear seats are large and deeply shaped for two adults but legroom, as with so many similar Grand Tourers, is poor. It shouldn’t be. A pleasant ride from firmish suspension, and comfortable front armchair seats offering a wide range of positions make the Jensen an easy, relaxing car to drive — except for “back-double” town work or parking when the steering is too heavy for comfort. We particularly liked the responsive, well-balanced handling and the strong signals from the steering which permit astonishingly carefree use of so much power. The roadholding, too, is good and the car remains impressively stable right up to its maximum speed. Disappointingly, severe use could fade the all-disc brakes of our test car and they also juddered a lot when hot. We were not impressed by the bewildering confusion of switchgear, either, and it is sad to reflect that £3700 does not buy a car immune from irritating minor ailments — like flickering interior lights and faulty electric window-winding mechanism. In concept, however, if not in every detail (and our test car was one of the earliest ones made) this Jensen is a splendid piece of engineering and very exhilarating to drive. We hope to supplement this test with our impressions of the more costly four-wheel drive Jensen FF (Ferguson Formula) version soon.

Performance and economy

Difficult starting seems to be something totally foreign to big American engines. Despite a rather lazy-sounding starter motor, the Chrysler V-8 fires instantly in sub-zero temperatures and idles immediately with a sweet burble on its automatic choke. There is no hint of hesitance or misfiring when pulling away with a cold engine and you can only tell when it is fully warm when the choke cuts out or the temperature gauge needle climbs to “N”. After the hot engine has been switched off, the twin thermostatic electric fans can be heard whirring away for a minute or so longer.

The red band on the rev counter starts at 5100rpm but few owners are going to reach it very often. Even on part throttle, the Interceptor can normally out-accelerate anything in sight with that silken surge so typical of a big V-8. On unrestricted French autoroutes we were cruising at a relaxed 110mph with still plenty of acceleration in hand: in fact the car would storm up to its maximum speed in a relatively short time and then suddenly level off with the rev. counter needle hovering just inside the red sector. Throughout its modest speed range, the engine is utterly smooth and normally very quiet though beyond 4000rpm the muffled, potent warble from the exhaust gives way to a more urgent hum from beneath the bonnet. Hydraulically operated tappets with no back-lash at all help to make the engine so quiet. On our 1-in-3 test hill the car shot away from rest with such verve that it practically took off at the top of the hump.

Needless to say, all this splendid performance must be paid for with large quantities of petrol. Checks throughout our long test showed a consumption of between 11 and 12mpg using 98 octane fuel (not the most expensive). On a 16-gallon tank this allows a modest range between fill-ups of under 200 miles — less if you top up when the useful low-fuel light starts to glow with about 3 gallons left.

Transmission

If there is anything more impressive than the engine it is Chrysler’s 3-speed Torqueflite automatic transmission which not only changes gear with imperceptible smoothness but allows the driver full overriding control. The stout console-mounted lever moves fore and aft through five positions — 1, 2, D, N and R. There was no P (for parking) on our test car though later models apparently have one. Normally, the fully automatic D range allows all the performance you want giving intermediate maxima of 36 and 70 (3500 and 4000rpm respectively). For more urgent squirts of acceleration you flick the lever back to 2 or 1, depressing a button in the top of the lever to do so, and then divert attention to the rev counter needle which swings round to 5100rpm — 53mph in first, 90mph in second — with astonishing rapidity. To change up, the lever is flicked forward without having to press the button. Although holding the gears like this makes the acceleration feel much faster, the accompanying figures show that the gains are in fact small so the lower holds are most useful for selecting a lower gear on, say, the approach to a roundabout or for preventing the engagement of a higher ratio—such as on a twisty road or, best of all, on an Alpine pass. Both the gearbox and final drive are inaudible.

Handling and brakes

Such power is wasted if it cannot be used safely so it is a tribute to the Jensen’s suspension, tyres and immensely rigid tubular chassis that some of our never-satisfied drivers were musing about the use of a 425bhp 7-litre “Hemihead” Chrysler by the end of our test. Undoubtedly, the Jensen could take it. Not once was any driver worried or embarrassed by a surfeit of power — not even on the packed ice and snow which our pictures proved we found on Luton Hoo’s private roads. True, it is fairly easy to spin the wheels in the wet or to break them away with a judicious thrust at the throttle on corners but the resulting power slide is easy to correct and hold to anyone who knows his skid drill. It is possible to circumnavigate a roundabout — or in our case MIRA’s steering pad — balancing excessive power against opposite lock with the back wheels scouring a path almost outside that of the fronts. We don’t recommend the practice but such fine control is an important characteristic of a powerful car like this.

With quiet, almost old-fashioned non-radial Dunlop RS5 tyres at their normal pressures of 24 p.s.i. all round, the rack and pinion steering is pretty heavy and lethargic (especially on slow, sharp corners) despite the big-diameter steering wheel. It becomes lighter and quicker with higher tyre pressures and was at its best when the car was set up for maximum speed runs with 36 p.s.i. in the front tyres and a prodigious 48 p.s.i. in the rears. With the carcasses as taut as this, they practically twang like a kettle drum on cat’s-eyes and bumps but on normal roads we did not find the ride unduly harsh. For everyday use, even if really high speeds were not used, in- between pressures would be preferable unless the car had power steering which is available at extra cost.

Whatever understeer the car normally has can be adjusted or over-ruled with the throttle, almost regardless of what gear you are in. Such roll-free response, together with a 50:50 weight distribution, splendidly progressive breakaway of the tyres on the limit, and enormous feel in the steering, encourages brisk cornering. As the handbook honestly observes, rough-road feel is fed to the driver as strong kick-back in the steering but we considered this an acceptable penalty to pay for the reassuring knowledge of what was happening at the front wheels in the wet.

Dual-rate rear springs that feel initially softer than those of the C-V8 contribute to the comfortable, level ride — by no means soft and floating but pleasantly stable as though the car flattens everything with brute weight (at 33 cwt, it is much heavier than the C-V8) or flits over bumps so smartly that they have little effect. The rear springs are controlled by Armstrong Selectaride adjustable dampers on ordinary roads we could not detect much difference between the first (soft) and fourth (hard) settings. On bad roads, the softer induced a little more float and pitch which some people may prefer to the otherwise quicker, harsher suspension movements.

The all-disc brakes, though normally progressive and reassuring, proved disappointing for really hard driving. During our fade test, pedal pressure rose from 45lb on the first 1/2g stop (from 84mph) to 75lb by the 10th. Although pressures actually dropped a bit after this, the brakes juddered angrily from the 8th to the 20th stop and felt anything but reassuring. An extra hard stop immediately afterwards confirmed what we had suspected throughout the test — that the brakes were in fact on the threshold of severe fade. They quickly recovered their former power and smoothness but later on, in France, they were again reduced to unpleasant juddering and high Trial pressures while attempting to keep station with a fast-driven American sports compact. Never did we expect to see a Detroit car out braking a British thoroughbred (though we have a sneaking suspicion that the brakes on our Jensen were perhaps not in such good order as they could have been). The handbrake just secured the car real 1-in-3 hill but it needed a very heavy pull to do so.

Comfort and controls

A more sloping cushion would improve the otherwise comfortable  front seats: as they are, most drivers complained a little of a tendency to slide forward. The driving seat does not go back very far but as the steering column has a telescopic adjustment, no one was cramped and a long-arm driving position is both possible and comfortable. The positions of the steering wheel, pedals, handbrake and gear selector — and their relative positions to each other — seemed to suit everyone. The seat squabs are fully adjustable but protruding door arm rests (which made uncomfortable knee rests for tall people) prevented easy release of the adjusting lever.

The comfortable rear seats are far more bucket-shaped than the front ones and so will accommodate only two people. Squabs that curve right round the wheel arches leave little room for your arm and legroom is also poor unless the front seats are pushed well forward.

Clearly, a great deal of thought and development have gone into the heating and ventilation system but a simple one could probably do the job better. In our experience, the best systems (Ford Cortina, Hillman Hunter, Mercedes-Benz) have only a few well-chosen controls: in the Jensen, there are no fewer than 24 different operations you can make to regulate the heating or ventilation. Briefly, there are two small vertical levers in the centre to control temperature and distribution and a third lever behind the steering wheel regulating air volume. Permutations of these three are often sufficient to give a pleasant atmosphere inside. But at low speeds in cold or wet weather various noisy fans must be employed — one for the big rear canopy that is very prone to misting up (embedded electric wires would clear it better), one for the interior and a third for the three facia vents (like those of a Hillman Hunter) with volume control vanes and twistable bodies. The two screen grilles, though of a different pattern, are similarly adjustable and there is also a separate foot-well ventilation system. The quarter lights are operated by awkward thumb screws, the main door windows by electric catches on the facia and the front-hinged rear extractor panes by levers. Individually, most of these are good things to have but collectively they rather over-complicate the system to such an extent that it is sometimes difficult to decide what to adjust.

Up to 80mph the Jensen is a quiet car: at higher speeds wind roar becomes fairly prominent but never loud enough to drown the push-button radio. Visibility is excellent and the dipping rear-view mirror scans a wide path behind. The lights are disappointing for such a fast car. They throw a diffused main beam which illuminates a big area dimly but nothing very brightly: an obvious case for quartz iodine conversion and perhaps supplementary spot and fog lights, too, for which unconnected switches are already provided. The steeply raked screen places the large sun visors quite close to the driver so it is difficult to swing them round to a side window without catching your head.

Fittings and furniture

Unlike the well-placed main controls, the Jensen’s switchgear is confusing and inconvenient: it seems to be a hallmark of several expensive grand tourers like this to have a central console bristling with switches but lacking in ergonomic design. The Interceptor’s saving grace here is that the two switches you use most — lights and wiper/washer — are the easiest to locate. The five instruments are well-sited, clear and readable, the two central ones (petrol gauge and ammeter) being angled towards the driver. What is more, the speedometer is dead accurate up to 110mph after which it becomes, unusually, pessimistic. A rheostat provides variable instrument lighting, including a warm glow from the gear selector labels.

The interior is very lavishly trimmed in black leather (an extra) which even smells expensive. Wilton carpet covers the floor, wood-capping’s part of the doors and facia, and the roof lining is of an unusual corrugated insulation. Standard equipment includes grab handles, ash trays (stiff to open) for all, coat hooks, two roof lights, front seat belts that tend to get tied up between the seats, a pushbutton radio, and a mirror-mounted map reading light which also comes on when the doors are open. There are red warning lights in the doors, too. Stowage space at the front consists of two meagre ledges under the facia, shallow but long map pockets in the doors, and a central locker which can be opened only by using the key that would normally be dangling from the ignition. At the back, deep lidded wells flank the rear seat (the left hand well holds the small first-aid kit), and there are more map pockets on the backs of the front seat squabs. The enormous platform behind the rear seat can be used as a temporary resting place — temporary because very- thing falls off when the boot is opened. This same shelf can be removed altogether, allowing the big boot to be piled even higher and also enabling rear seat passengers to reach luggage from inside the car.

Servicing and accessibility

Most of the jobs needing routine attention are done at 4000 or 8000-mile intervals but, unexpectedly, there are six nipples altogether — on the king pins and lower front suspension — that need greasing every 1.000 miles. By current standards, this seems an unacceptable demand for what is essentially a long-distance car. The crowded engine compartment is automatically illuminated at night (so is the boot) and the dip stick, oil and radiator fillers, and twin brake fluid reservoirs are within easy reach. A comprehensive set of tools is tucked away in a boot cubby and the stout, pillar screw jack is easy to place and operate: swing-away metal plates cover the four sill jacking points. The spare wheel is housed in a tray beneath the boot and is released by turning a screw with the wheel brace.

MAKE : Jensen.

MODEL: Interceptor.

MAKERS: Jensen Motors Ltd., West Bromwich, Staffs.

Maintenance summary

Every 1,000 miles — Grease king-pin bearings and lower front suspension.

Every 2,000 miles — Check brake fluid reservoirs.

Every 4,000 miles — Grease steering rack, brake balance lever, rear wheel hubs; drain and refill sump; check and top up steering dampers and front shock absorbers: check and top up rear axle; clean and check alternator; oil door locks, hinges, etc.

Every 8,000 miles — Clean air filter element and oil filler air cleaner; clean and check distributor points and sparking plugs; check crankcase ventilator valve; replace oil filter element; lubricate manifold heat control valve; check and top up automatic transmission: inspect prop shaft u/js for leakage: lubricate choke shaft.

Every 12,000 miles — Drain and refill rear axle; tune engine.

Every 16,000 miles — Check front wheel hubs and repack if necessary.

Every 20,000 miles — Replace sparking plugs; replace fuel pump inlet filter.

Every 32,000 miles — Clean and repack wheel hubs; replace air cleaner element.

Every 36,000 miles — Drain, refill and adjust automatic transmission; replace automatic transmission oil filter.

Insurance

1, electric thermostatic fans.

2, fuses.

3, radiator filler cap.

4, alternator.

5, distributor.

6, carburetter.

7, brake servo.

8, twin brake reservoirs.

9, electric screen washer bottle.

10, oil filter element.

11, oil filler cap.

12, dip stick.

13, battery.

AOA Group rating 7

Price in 1967 £3,043 plus £699 purchase tax equals £3,742.

Automatics tested by Motor

Jensen Interceptor  £3,742

Jensen C-V8 (5.9-litre) £3,392 when tested

Iso Rivolta £5,250

Jaguar MkX (now 420G) £2,380

Oldsmobile Toronado £4,759

Pontiac GTO £3,474

Gordon Keeble £4,058

Aston Martin DB6 (Vantage) £5,084

1 petrol gauge.

2, radio.

3, air vent.

4, ammeter.

5, speedometer.

6, total and trip mileage recorders.

7, main beam tell tale.

8, screen demister outlet.

9, oil pressure and water temperature gauge.

10 and 32, indicator tell tales.

11, rev. counter.

12, low fuel warning light.

13, dock.

14 and 29, electric window controls.

15, cigar lighter.

16 and 26, extra light switches.

17, panel lights.

18, rear window demister fan.

19, temperature control.

20, gear selector.

21, Selectaride control.

22, air distribution.

23, two-speed heater fan.

24, facia vents fan.

25, lights.

27, wipers and washers.

28, ignition/starter.

30, air volume.

31, trip re-set.

33, horn.

34, indicators and flasher.

35, air vent.

Deeply contoured rear seats provide comfortable accommodation for two adults but leg room is poor if the front seats are well back.

Fully reclining front seats allow the passenger to relax in real comfort. The central locker can only be undone with a key normally hanging from the ignition key ring.

The front lever adjusts fore and aft movement, the side one squab rake. The small button on the chrome hinge alters the squab’s spring loading.

Which one? The central instrument console presents the driver with a confusing array of switches. The gear selector is very well placed.

One of the five fresh air vents: the three on the facia have vane volume adjusters and twist in any direction. The driver’s left hand is adjusting the telescopic steering column release ring.

The massive counterbalanced rear window opens up like the jaws of a giant dam to reveal a big, carpeted boot. A total of 8.8 cu. ft. of test boxes fitted inside but there is room for more if the black boot lid cover is removed. The spare wheel is lowered from below on a tray by winding a screw in the boot. A good tool kit and first aid box are standard equipment.

The rear glass canopy mists up easily but can be cleared quickly by air blast; it then provides splendid visibility. This window is really a lid to the big boot underneath.

(Below) Striking steel bodywork (it used to be in glass fibre) is by Superleggera Touring. The magnificent five-stud chrome-trimmed cast wheels are standard.

Figures taken at 3,300 miles by our own staff at the Motor Industry Research Association proving ground at Nuneaton. All Drive-my test results are subject to world copyright and may not be reproduced in whole or part without the Editor’s written permission.