The Motor Sport Road Test -- Jaguar XJ6 3.2

Suave Speed

" Dear Sir/Madam, Your new D luxury car need not cost the earth. Especially if it is one of the new 1991 Jaguar saloons. This range features a new catalyst exhaust system and, for more spirited driving, an exciting sports handling pack is available as an option." The "junk mail" letter, addressed to the writer from what is now Lancaster Jaguar Reading Ltd. was an aggressive missive, spattered with capital letters, but it was also a welcome reminder; a prompt as to the continued value for money offered in the latest XJ6 series, which are priced from Ford Scorpio levels, from £23,750 upward.

The beautiful, dark green Jaguar XJ6 3.2-litre residing in our care was the most impressive of the XJ family we had tried since a similarly shaded XJC V12 coupé passed all-too-briefly through our hands in 1976. The 1991 model came complete with West German Getrag five-speed gearbox and the expensive (£2900), but effective Sports Handling Package mentioned in that sales letter.

The result is a combination of the smoothest power yet extracted from the comparatively young AJ6 engine series, handling that allies firmly Teutonic damper discipline with pampered British luxury ride at speed, and a driving appeal that remains the preserve of Jaguar in the blending of civilisation with speed. Certainly there are snags, items that we explore in detail below, but the 3.2-litre Jaguar XJ6 is a triumph of evolutionary engineering, one which deserves a wider buying audience than our current economic climate allows.

Although the angular current outline for the XJ6 saloon remains as it has since the original was superseded in October 1986, engineering progress on the in-line AJ6 replacement for the hallowed XK motor series has been made. Jaguar has now replaced the original 2.9 and 3.6-litre units with 3.2-litres and 4-litres. The 3239cc unit marks the most significant customer step, for the old 2.9-litre and its two valves per cylinder layout were not really up to the task of propelling a substantial chunk of Coventry metalwork with the grace and pace anticipated by customers in this category.

Technical Analysis

Based closely on the 4-litre unit, the Jaguar 3.2 has markedly superior power and torque in the now standard catalytic convertor trim. Compared to its 2.9-litre predecessor, both output figures for the 3.2 are increased by more than one third, both developed at slightly lower crankshaft rpm. Jaguar engineers point proudly to the fact that output and consequent performance is comparable to that of the earlier 3.6-litre unit, but most potential buyers will also be glad to know that Jaguar generally offer more power for less money than their BMW and Mercedes 7-series and S-class (publicly replaced at the March Geneva Motor Show) opposition. From the subjective customer's viewpoint, it is also worth knowing that the shrunken 4-litre Jaguar engine has the smoothest power delivery of any of the variations on the AJ6 theme that Jaguar have yet offered.

Compared to the 4-litre unit, a 3.2 shares the bore dimension, but the stroke shrinks from 102 to 83mm. It is still slightly biased toward a longer stroke, but this abbreviated stroke and its associated replacement 9.75: 1 pistons and connecting rods could be a strong contributory reason for the AJ6 unit reaching the standards of refinement that were lacking when this engine series made its debut in 3.6 XJ-S coupes. It is also encouraging to note that the crankshaft, like that of its 4.0 elder brother, is now of steel and the cylinder head is a shared 4-litre item with twin overhead camshafts activating 24 valves.

Other hardware that is interchangeable between the 3.2 and 4.0 includes the "twin low loss catalyst exhaust" and recalibrated Lucas electronic management of fuel injection and ignition. The latter was not satisfactory in the manual transmission car of our performance tests, but we do not think that it was a general fault as three other 3.2-litre models that we have experienced ran faultlessly at all engine rpm. The examples we drove in the winter of 1990/91 were all equipped with the optional limited slip differential, a multiple plate unit that is standard upon the Sport suspension option that we assessed or a worthwhile £250 option. Our test car was performance tested in 5-speed manual form, but there is an £850 option for the also West German sourced ZF4HP22 4-speed automatic, which we found entirely satisfactory in alternative Jaguar press fleet examples.

In the latter case the "Randle's Handle" dual gate transmission (named after development chief Jim Randle) provided a convincing lower cost contrast to the Porsche Tiptronic transmission. It has acceptable performance and economy losses for those who have to motor to the centre of a city on a daily basis, and provides a measure of manual gear selection that is noteworthy within the constraints of a conventional automatic gearbox. Externally the Sports Handling Pack's presence is most obvious from a slim coachline and broader 8 x 16 inch "forged lattice" styled alloy wheels. These are from Germany, but are not the product of the inevitable BBS factory; rather the forged aluminium process should be familiar to some Porsche owners, because these Jaguar wheels are from Fuchs. The tyres sound like familiar Pirelli P600s, but Jaguar engineers under the ride and handling leadership of Mike Cross have co-developed a cover unique to Jaguar. Its 225mm breadth was described by engineers as, "the largest we could fit under our wheel arches with an 8mm legal clearance that no aftermarket system can offer."

Little is now said about the relationship with Tom Walkinshaw Racing (TWR) and the JaguarSport co-owned company which already offers a series of modifications for the Jaguar range. From the individual path that Jaguar Engineering have trod on XJ6, and the XJ-S sporting suspension, we can take it that the company still feel they can provide a less radical customer alternative "in-house".

Important suspension changes centre upon substantially increased coil spring ratings. Up front the rise from 56N/mm to 84N/mm represents a sharp 50 per cent step toward firmer control. The rear is not so radical, just 11 per cent elevated from 72N/mm to 80 N/mm. Front and rear ride heights are reduced by a minimal 15mm/0.60 inch and 10mm/0.4 inch respectively. The stiffer suspension philosophy is also extended to a 58 per cent bonus in front anti-roll bar action and unspecified "tuned to suit" detailing of shock absorber valving "reducing float and pitch." At the unfortunately unchanged steering wheel an increase in spring rates and subtle "steering rack mounting and control valve modifications," supply the majority of sporting information and pleasure to the driver.

Action

Despite spluttering from 5000 rpm upward to the tachometer warning line of 5500 rpm, the 1.77 ton Jaguar performed entirely in line with its maker's claims. The maximum speed is unlikely to impress the Germans at little more than an honest 130 mph (208 kph). However, we were impressed by a 0-60 mph time of less than 9 seconds, for it was achieved in damp conditions that endorsed the effectiveness of the limited slip differential and Pirelli tyres, being within 0.4 second of the manufacturer's claim in perfect conditions. Not unexpectedly the latest 3.2-litre also lies within tenths of the performance levels achieved by the pre-1989 3.6-litre Jaguar XJ6. The Jaguar was happy to romp up to 110 mph on our one mile test straight in little over half a minute.

Under stress, the gearchange remained the amiable and accurate friend that we had also discovered when ambling through London traffic. Gone are the days of big car/truck gearbox engineering strategy, thankfully. The six black and white dials lie unhappily alongside the green digital displays of mileage and computed information (average speed, fuel consumption, remaining fuel range and so on). However the large 150 mph speedometer and 7000 rpm tachometer do reveal the long striding ease of Jaguar performance.

A 100 mph pace is delivered without power train stress at marginally less than 4000 rpm, but at this point the body does begin to allow wind noise to intrude. Even so, the police will doubtless testify to the number of Jaguar drivers they find in the 100 to 120 mph bracket who simply "didn't realise how fast I was going, officer." It really is a very deceptive car in which to judge cruising speed, and we would unhesitatingly pick the 3.2 XJ6 as a long distance journeyman, although our 15.5 mpg average would allow less than 300 miles between safe refuelling points.

That figure betrays the fact that the performance session was included, a subsequent Oxfordshire to Birmingham brim-to-brim fuel check revealing 16.4 mpg; the computer was not the most accurate we have used, optimistically reporting 18.3 to 22.7 mpg to emphasise the varied mileage tackled.

The straight six cylinders sounded delightful in the 2000 to 4000 rpm band, gradually slipping from the urbane cough of an English butler to the civil echo of past motor racing glories, especially when extended beyond that 4000 rpm guideline.

Jaguar standards of cabin luxury were emphasised by extensive use of walnut veneers, these conquering the fascia, central console and doors in an exploratory manner that is unmatched by brands beneath the Rolls-Royce/Bentley sector. The test car was superbly finished with an optional £600 leather trim that suits the Jaguar character well, a compliment that cannot be paid to the determined heavyweight plastics of a bulky two-spoke steering wheel, or the cheap-calculator appearance of LCD (Liquid Crystal Display) digits.

The controls are individual, but inefficient because of that determination. For example, the light switch is unlike that of any other current car, operating on a rotary switch that hides on the edge of the instrumentation cowling, whilst the flashing indicators are still activated on the "soft touch" system that omits the basic safety measure of self-cancelling. Also clumsy is the provision of two internal light switches and the ventilation is complicated by the use of "mode" buttons to divert air to driver or screen. Once mastered, the system is effective, as is the 9-button computer, but the marriage between tradition and the era of electronics is unhappily arranged.

Apparently, an enormous three year effort was devoted to the Jaguar and Alpine co-operative design and installation of radio and cassette player. We spent an inordinate amount of time listening to Pavarotti and a popular medley from the depths of the boot-mounted Compact Disc player unit, all because we simply could not drive safely and tune the unit to the stations required. Redeeming aspects are high quality sound and thorough integration into the centre console.

Once in motion, such carping ceases. The engine swiftly settles to an even 900 rpm idle and progress up to a mile a minute is almost spectral in its unearthly ease. The test car makes its presence known through the modest feedback of stiffened suspension at town speeds, the steering responding to bumps and adverse cambers with the mildest of tugs upon the steering rim.

Exceed 35 to 40 mph and the sporting Jaguar suspension accommodates bumps with grace, never allowing its long wheelbase to be shifted out of line by such obstacles. Increased steering sensitivity and broad tyres allow the Jaguar driver to know that this sports suspension example is travelling over a road surface, rather than floating in ethereal numbness, but anyone bred on BMW or Mercedes ride and handling characteristics will merely feel that Jaguar comfort has been complemented by a long overdue return of driving pleasure. The sporting suspension proved impressive in conditions that exercised the limits of the single front screen wiper. When the Oxfordshire and Northamptonshire lanes were awash with standing water, the Jaguar was not embarrassed. It almost bore comparison for unflustered downpour progress with the now (sadly) obsolete Audi 20v quattro turbo that was our Christmas transport.

The writer was genuinely surprised by the effective traction from a standing start, although provocative tactics would always ultimately reveal that power, or more importantly torque, does arrive at the rear wheels in sufficient quantities to yield wheelspin. Stability over standing water was exemplary and the reporter drove another (automatic) example over ice and snow without noticeable increase in heartbeat.

Where the Jaguar is not so confident is at speed in motorway crosswinds, passage past heavy lorries requiring notable reflex action at the steering rim. Previously, we might have hesitated to describe Jaguar XJ6 handling at all, for who amongst those automatic transmission saloon customers truly explored the limits of their comfortable steeds? Now the adhesion of lower profile rubber can be exploited enjoyably and the near 4000 lbs barouche sheds its parking clumsiness for a turn of country road speed that has not been offered in production Jaguar saloons since the era of the 3.8-litre Mk II.

Verdict

Even the addition of more than £4000 in extras does not disguise the extraordinary value that Jaguar Cars continue to offer under their new ownership. In fact the starting price of £23,750 is a positive embarrassment to many mass producers, including Ford who have more expensive Scorpio derivatives in their range. Jaguar also continue to offer a unique blend of civilised speed that many seek to emulate. Meanwhile, the engineers at Allesley hint that they would see a more sporting edge to their range in the firmly controlled ride of the test car.

Styling is a subjective matter, but the writer feels strongly that the company should have been braver in the evolution of the XJ6 body; it badly needs to be lighter and sleeker to maintain the Jaguar reputation competitively in this sector; a reputation that is deserved in 1991 and one that reflects full credit on the Jaguar Cars engineering team. Unfortunately life is unfair and their World class product may suffer from adverse factors outside their control. Toyota have already displayed an aptitude for silent travel in the large Lexus that has furrowed a few executive brows at Jaguar Cars. This worrying Oriental competence, plus an extended Gulf war, could leave Ford and the new Jaguar car buyer equally embarrassed over the resale price of large luxury cars. -- JW

***

MOTOR SPORT TEST RESULTS: Jaguar XJ6 3.2 (manual)

Test conducted at Millbrook Proving Ground using 1990 Correvit electronic measuring gear. Weather conditions: Damp, overcast.

ACCELERATION (mph....seconds):

0-30........2.9

0-40........4.6

0-50........6.4

0-60........8.9

0-70......11.4

0-80......14.5

0-90......18.9

0-100....24.1

0-110....32.9

GEAR SPEEDS, mph at 5500 rpm:

First: 35.1; Second: 50.4; Third: 76.0; Fourth: 107

FLEXIBILITY (50 - 70 mph):

Third gear 4.9 seconds; Fourth gear 8.1 seconds; Fifth gear 12.9 seconds

Standing 0.25 mile/400 metres: 16.5 seconds at 84.5 mph

Maximum speed: Millbrook 2 mile bowl: 128.7 mph

Best observed speed: 131.5 mph

Overall Fuel Consumption Test: 15.52 mpg

Government mpg figures: Urban -- 17.9 mpg; at 75 mph, 29.1 mpg; at 56 mph, 36.2 mpg

SPECIFICATION

ENGINE: Water-cooled, light alloy in-line six cylinders and DOHC 24-valve cylinder head. Capacity: 3239cc (91 x 83mm). Lucas electronic ignition and fuel management: 9.75: 1 cr.

Max power: 200 bhp @ 5250 rpm. Peak torque: 220 lb ft @ 4000 rpm

TRANSMISSION: Getrag 5-speed. Rear wheel drive. Salisbury limited slip differential. Final drive, 3.77:1

BODY: Steel monocoque 4-door saloon. Petrol tank of 86.4 iitres/19 gallons.

Drag coefficient 0.37Cd.

DIMENSIONS: Wheelbase 113 in/2870mm; front track 59.1 in/1500mm; rear track 59 in/1498min; width 79.3in/2015mm; length 196.4 in/4988mm; height 54 3 in/1380rnm.

Kerb weight: 3969 Ib/1800 kg.

FRONT SUSPENSION: Unequal length wishbones, uprated Sport Pack coil springs and revalved telescopic shock absorbers; 23mm Sport Pack anti-roll bar plus ride height lowered 15mm. Steering: Power assisted. 2.8 turns lock-to-lock, rack and pinion. 40 ft 8 inch turning circle.

REAR SUSPENSION: Lower wishbones and driveshaft utilised as upper link in independent layout; uprated Sport Pack items: concentric coil springs and telescopic dampers, ride height lowered 10mm

BRAKES, WHEELS, TYRES: Hydraulically power-assisted; vented 11.14 inch/283mm diameter front discs, solid rears of 10.35 inches/263mm; Alfred Teves electronic anti-lock braking. Light alloy 8J x 16 inch front wheels, 8J x 16 rears. Pirelli P600 225/55 ZR 16.

PRICE: £23,750, UK taxes paid. Priced options on test car were: Sport handling package, £2900 (includes limited slip differential, replacement wheels and tyres, plus coachline and self-levelling ride height); headlamp power wash, £350; leather trim, £600; Compact Disc player, £560. Total car price with options, £28,160.

MANUFACTURER/Importer: Jaguar Cars Ltd., Browns Lane, Allesley, Coventry. CV5 9DR

CLAIMED PERFORMANCE: Max speed. 132 mph; 0-60 mph 8.5s.

Our thanks go to Corinna Phillips of Silverstone Circuits, Tom Walkinshaw Racing personnel for allowing us to photograph the exciting new Jaguar/TWR XJR-15 and our test XJ6 at the official opening of the new Grand Prix layout.