New cars

Aiming to be World class

If Sir John Egan mentioned the expression ‘world class’ once during the recent Scottish launch of Jaguar’s new 4 litre version of the XJ6, he mentioned it 30 times.

“Jaguar must learn to become world class,” – “Our problem is that we are not operating in a world class economy, like that in Japan or Germany, we are seeking world class suppliers, and our problem is that we are a small volume manufacturer, the only one in Britain producing this sort of car.”

It isn’t paranoia; it’s awareness. Awareness, as it has been since he first spelled out his line of attack back in 1981, of Jaguar’s strengths and its vulnerability.

The famous Coventry marque is currently fighting off any need to climb back into bed with a monied partner; it’s been that route with Leyland, and still counts itself lucky to have escaped back into private ownership.

In one respect, Sir John has a little less to worry about. The latest XJ6 – only just launched – really is a world class contender in the increasingly popular and lucrative luxury saloon market sector.

It is only in retrospect that the cracks in the original ‘new’ XJ6 launch structure, back in 1986, become clearer, and then only through the company’s own admission. “We had to change an awful lot on the XJ40 cars due to the lack of engineering development on the original cars in the Seventies,” says Communications and Public Affairs Director David Boole. “There was very little we could carry over.” There were things that had to be incorporated because of the schedule, but they rankled.

At the time money was tighter still, the braking system was a compromise, the engine was relatively noisy. Many minor details were below the desired optimum. Three years on, those `faults’ have been rectified. “We certainly have enjoyed great success with the XJ6 range since its launch in 1986,” says Sales & Marketing Director Roger Putnam. “We also know that if we are to remain a world class luxury car maker and continue to grow we must continuously develop and refine our products.”

The increase in engine capacity, of course, is the most significant. Jim Randle’s straight six AJ6 powerplant has come a long way since its early days of camshaft glitches, and is a worthy successor to the legendary XK. “Our main thrust,” says Jaguar’s technical chief, “has been to improve acceleration while maintaining the same level of fuel economy, and we have achieved that by a much better management system and a new four-speed auto box.”

The latest XJ6 retains the original’s allaluminium structure, four-valve pentroof combustion chambers and Duplex chain camshaft drive but now has a longer stroke. This is up from 92 to 102mm, for a cubic capacity increase to 3980cc, and besides enhancing torque by a useful 14% (285 lb/ft at 3750 compared to 249 at 4000), that also ups the power to 236 bhp at 4750rpm, compared to 221 at 5000. Just as significant is the reduction in parasytic loss (now only 5%) on cars fitted with catalytic converters. This has been achieved by a special low loss’ exhaust system and puts Jaguar in an ideal position ready for the day when the British market embraces catalysts wholeheartedly.

What is also impressive about the catalytic cars is that the 10 bhp difference between the two is a maximum figure, and power. train chief Trevor Crisp is confident that there is considerable overlap in power outputs.

Sir John spoke enthusiastically about the manner in which Lucas — once a leading supplier of exhibits in the Jaguar `Black Museum’ — has improved its products, and the 4-litre engine uses the Birmingham concern’s digital electronic multi-point injection system and electronic ignition pack. This has improved starting, idle speed control, diagnostic capability (24 functions monitored against 9 originally) and allows interface with the automatic transmission, so that ignition timing can be retarded during gearshifts. The unit outputs a calculated engine torque so the transmission’s control system can optimise the shift quality.

The resultant improvements in drivesbility are complemented by some significant internal changes. A new piston design reduces inertia, while the crankshaft is now forged in steel to increase strength and torsional stiffness and reduce vibration levels. Revised cam profiles help to improve torque and improve the idle smoothness.

Jaguar sells many more automatics than manuals, and the XJ6 now boasts ZF’s excellent 4HP 24E four-speed unit which will be familiar to many BMW owners. As usual this has the ‘Normal’ and `Sport’ modes, achievable by actuating a switch on the centre console, and the excellent J-gate ‘Randle handle’ gear lever is maintained.

‘Normal’ mode is designed for everyday motoring, while `Sport’ makes the transmission more sensitive to throttle openings and holds on significantly longer to each gear during hard acceleration. “It creates a real Jekyll and Hyde character,. says Randle. Due to the greater power and torque of the 4-litre engine, Jaguar has specified the Getrag 290 manual gearbox (the number refers to he torque capacity) in place of the 265. Other improvements are the twin-mass flywheel, which damps out torsional vibrations and shock loads, and a larger diameter clutch. Where performance is concerned, the technical improvements have boosted the maximum speed of the manual models to 140mph (136 for the 3.6 predecessor) and the 0-60 time falls from 7.4s to 7.1s. The autos remain slower, as one would expect, with 138mph top speed and 0-60 in 8.1s.

The time since the launch of the 1986 models has been spent wisely, and the 1990 cars now have an all-new Teves braking system, with an anti-lock facility standard across the world range. The front discs have also been increased in size slightly. Enhancements are evident throughout the car, but surely the most popular has been the cloaking of the electronic equipment behind the fascia with traditional analogue instruments, following vociferous customer requests.

There are new door handles fitted with Tibbe high security locks, the boot can be opened visa remote release in the glovebox, all locks and the ignition now function from one key, which is smaller (although the (original must therefore have been a monster!), and there are another five new exterior colours for 1990 including three new rnicattalics.

The 2.9-litre cars continue with the same engines and transmissions but the other 1990 improvements, and the XJ-S won’t get the 4-litre engine just yet.

Prices start at a competitive £21,290 for the XJ6 2.9, then proceed to £25,200 for the 4-litre, £28,000 for the Sovereign 2.9, £32,500 for the Sovereign 4.0 and £36,500 for the Daimler 4.0.

One’s immediate initial impressions of the 4-litre XJ6 are that both the clutch and the gearshift are heavier than on equivalent BMWs, but it is also obvious that the revised engine is markedly quieter and smoother. Part of the former is due to copious user of new Teroson sound-proofing material, but the valve thrash of the original four-valve engines is now a thing of the past and so is the associated rasp. A pity in a way, but although the engine has always been one that lets you know it’s working, the 1990 cars certainly are on a par with the market best in the noise suppression department now.

The increased torque and power are also immediately evident, and for a hefty car the XJ6 pulls like a train up through the gears. Feeling a trifle jaded, we began our tour of Scotland’s gorgeous countryside with an automatic, and having satisfied ourselves with a quick burst in ‘Sport’ mod, left it to its own `Normal’ devices. Apart from feeling that the gearlever was sloppier than we remembered from the 1986 cars, no complaints here, but plenty of praise for behaviour during full throttle upchanges.

Later, a manual confirmed our suspicions that top gear flexibility has been enhanced greatly, thanks not only to the increased power and torque, but also to the flatness of the torque curve and the amount developed at the engine’s low-rev range. The gearlever is set a little further back, which should please shorter-armed drivers.

The damping, markedly better than the old Series III cars, is firmer still, thanks to minor tuning of the rates, and the car is all the better for it, tackling poor surfaces with aplomb and maintaining its poise over undulations and when pushed into corners. The brakes also have a better feel and performed better from high-speed stops.

From our brief excursion we would have little hesitation in confirming that the new Jaguars are now fully on a parr with comparable offerings from BMW and Mercedes in all respects bar their somewhat dated looks. DJT