As John Egan remarked to us at the Geneva Show, racing is part of Jaguar’s heritage. A carefully planned European Touring Car Championship programme brought the Coventry marque five outright successes last year, with engineering expertise and part of the budget coming direct from Jaguar, the build, development and race programme handled by the astute Scotsman, Tom Walkinshaw.
Neither Renault nor Alfa Romeo find that success on the race tracks directly benefits sales of family cars, since their customers perhaps realise that a 700 bhp Formula 1 car and a 90 bhp family saloon are likely to be as far apart as the sun and the moon. For them, racing creates an image. For Jaguar racing creates an image too, but in the world markets, and particularly in Germany, victories with the XJS are bound to be linked to sales, and current registration levels tend to bear this out.
Tom Walkinshaw, whose engineering and driving skills have done wonders for Mazda and BMW in Britain, has built up a successful business out of making road versions with higher levels of performance, so it was only a matter of time before he developed a high performance version of the XJS, the end result being announced at the Brussels Show in January.
The TWR Jaguar XJS is aimed at a specific market occupied by the Mercedes 500 SEC, the BMW 635 CSi, the Porsche 928s, even the Ferrari 400i and the Aston Martin V8, with prices as diverse as £24,000 and £44,000. When people buy a car costing that much is isn’t so much as the model they select as the image they wish to project, so value-for-money and levels of equipment hardly come into the equation; all creature comforts are assumed.
In this sector of the market, accounting for perhaps 2,000 registrations annually, only the £43,000 Aston Martin V8 is made in Britain, so it isn’t lack of patriotism which makes foreign cars so dominant, but simply lack of choice. Priced at £34,700 therefore, the TWR seems well equipped to take slightly less than ten per cent of this particular sector, with production pitched at three cars a week from Walkinshaw’s base at Kidlington, near Oxford.
Another thing that’s common to this market is very high performance, the average maximum speed of this group being 147 mph and the average 60 mph acceleration time being 7.1 seconds (not all that fast, but a couple of them are available only in automatic form). The TWR Jaguar, on the other hand, is available only with an extremely nice ZF 5-speed transmission and is fast enough to run rings around most of its rivals, having a claimed top speed of 164 mph and a 0-60 mph time of 5.8 seconds. Above all, though, the sheer flexibility and smoothness of the balanced and blue-printed 5.3-litre V12 engine offers a new experience in motoring. In a back-to-back test we imagine that the modified Jaguar would be about level pegging with the Series 2 Porsche 928S as regards acceleration and top speed, and that German car would be its nearest competitor.
Tom Walkinshaw and his marketing director, Patrick Eggs, set out to develop the XJS in such a way as to enhance its good points without spoiling any of the creature comforts. The engine modifications which, together with the new heavy duty stainless steel dual exhaust system account for a power increase of around 10% (to approximately 320 bhp), in no way impair the power unit’s flexibility.
The suspension is extensively reworked with Bilstein gas shock absorbers, higher rate front springs and lowering, by three-eighths of an inch at the front and five eighths of an inch at the back, resulting in a noticeably firmer ride which is still very acceptably comfortable at lower speeds, but makes the XJS feel altogether more controllable in high speed bends or tighter corners, improved turn-in and less roll being the prime features. Speedline wheels from Italy in cast alloy, 8 ½ in section and of 16 in diameter, can be supplied with Goodyear Eagle or Pirelli P7 tyres with 225 or 245 section and VR rating. In themselves the wider wheels and tyres must account for a slightly higher level of noise and bump-thump on urban roads, but the standard product is so boulevard that the suspension could stand some sporting modifications without spoiling its essential characteristics.
The power assisted rack and pinion steering system is left alone, apart from the smaller diameter TWR leatherbound steering wheel which is fitted, so the other major area of modification is in the braking department, where new ventilated discs are fitted all round, with TWR designed alloy callipers. At the front the disc size is increased to 11.625 in, the width to 1.4 in, while at the rear the discs are up to 10.625 in and 0.78 in width.
The engine, gearbox and brake modifications will be offered by TWR as a complete package, preferably on a new car, but the high quality styling package may be offered through selected Jaguar dealers in response to an already brisk demand. Unlike many of the body kits available today, which go beyond the bounds of good taste, the TWR kit designed by Peter Stevens undoubtable enhances the TWR’s graceful styling, updating it might be a better description, involving a reinforced moulded front air dam and spoiler, a matching rear panel, side skirts, and a discreet rear wing which is large enough to do a man’s job without making the Jaguar look too racy. Wind tunnel tests have shown these body parts to reduce front-end lift by 60% at high speed and rear lift by no less than 88%, whilst the drag figure is lowered by 12.7%.
Completing the transformation is a new interior with Scottish tweed and high grade leather replacing the original seat materials, the steering wheel already mentioned, and further work would be available at extra cost. The demonstrator car we drove was finished in light blue metallic with silver lower panels, and was one of the most attractive looking cars we have seen for a long time. Maybe the twin headlamp system used on the US specification cars, and on the Jaguars raced at Spa last year, would be a further improvement, but that would be a matter of personal choice.
Ticket to ride
Though much of the development work can be traced to race preparation the TWR Jaguar remains a superbly drivable car on public roads. The clutch is smooth, the gearbox light to use though, for choice, we would like a more clearly defined gate for third and fifth, or stronger helper springs.
Twin tailpipes on either side at the rear appear through tailor-made apertures in the bumper section, and the custom-made freeflow exhaust system has a nice healthy growl which doesn’t rise to offensive levels. From the outside the XJS looks and sounds a little more aggressive than normal, while the occupants might notice a slightly higher, but altogether pleasant level of engine noise.
The XJS is not normally available with manual transmission, but the ZF box seems an entirely natural choice to mate with the V12. The lower ratios are fairly closely matched while the overdrive fifth is geared to 31.5 mph per 1,000 rpm, relating to 5,200 rpm at the claimed maximum speed.
The rate at which the TWR converted model eats up the miles is quite astonishing. Like a true high performance car it reaches 100 mph in around 15 sec and keeps on going, pulling strongly to 130 mph and much more, given the space and the state of the driver’s licence! We have noted that the standard XJS has much the same levels of noise at 70, 100, or 120 mph, and the same is true of the converted version which, with a kerb weight of 1,700 kg (34 hundredweight) is up into the heavyweight class.
The aerodynamics must be good, though no standard figure is quoted, to attain a maximum of speed of over 160 mph with some 320 bhp at the flywheel, since the 928S with 310 bhp and weighing 28 ½ cwt also has a claimed maximum of 164 mph (and has proved it at the Nardo testing ground). Such statements are largely academic, merely representing the performance capability, but they matter rather more in Germany.
What we did establish in a morning is that the TWR Jaguar is sufficiently advanced to be hailed as a breakthrough into the supercar class. Good as the standard model is (and at a price inside £22,000 it still represents excellent value for money) the performance is just below the threshold of supercar, the handling well below, Walkinshaw’s handiwork has changed that, for the TWR XJS is a car that we’d be happy to match against any of its rivals on acceleration, high speed performance, handling and braking.
Three cars in a week may well not be enough, particularly when exports to Europe get under way. The TWR-modified Jaguar will be available through about 10 selected UK dealers, yet to be named, and will carry a full warranty either from Jaguar or from TWR, depending on whether the claim relates to standard or modified parts. We would like to re-state that the TWR XJS is prepared to a very professional standard, one which the Jaguar factory approves of, and were it to be announced by Jaguar as a new model a discerning public would be clamouring for it. Tom Walkinshaw’s creation deserves no less an enthusiastic reception. – M.L.C.
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