Jaguar XKE Series 3 V-12


The Jaguar XKE Series 3 V-12 was Jaguar's response to the emasculation of its classic XK inline six-cylinder engine by emissions regulations.

The Jaguar XKE Series 3 V-12 was launched in 1971 and replaced the XKE Series 2 and its 4.2-liter six. This was a new breed of sporting cat, and it looked it.

Jaguar Image Gallery

The 1971 Jaguar XKE with V-12 power.
Its classic inline-XK six enfeebled by emissions
regulations, Jaguar turned to V-12 power for the
XKE in 1971. See more Jaguar pictures.

Among alterations accompanying the move to the Jaguar XKE Series 3 V-12 were a larger radiator inlet screened by formal grillwork and the addition of subtle wheel arches to clear wider tires. The signature hood bulge was retained, even though it wasn't needed to clear the new engine.

On paper in 1971, the move to a V-12 was a fabulous idea. The once-supernatural XKE was 10 years old and had lost some of its magic. At 23, the once-mighty XK six-cylinder engine had lost some of its power to emission controls. To recapture the horses, Jaguar was developing a much larger, all-new motor for its sedans. So why not introduce it in the sports car and see if some of the XKE magic could be recaptured, as well?

After all, the ploy had worked back in 1948, when the all-new XK-six-powered Jaguar XK 120 had created an aura of performance prowess-and, not incidentally, some real-life service experience-by debuting a powerplant principally designed for the Jaguar Mark VII sedan.

This time, perhaps the aura of an all-new engine might return the favor and juice up the image of the XKE, a sports car now all too familiar.

And so in March 1971, Jaguar unveiled its long-rumored "new" sports model. Contrary to logical expectations, it was not called F-type but XKE Series 3. But who cared? What mattered was that it was motivated by the anticipated, wondrously exotic V-12.

Unfortunately, this "V-12E," as some called it, would never really replicate in the early 1970s the epic era of the original XKE in the early 1960s. And that was not entirely Jaguar's fault.

Creating automobiles used to be the purest pleasure. In the very early days it was a scientific activity, the entire focus being on the basic task of getting the newfangled contraptions merely to run, let alone reliably. Once the mechanical side was in hand, a maker was free to pursue the thing as an artistic endeavor, building machines top lease itself.

That quickly merged into its becoming a commercial enterprise, making cars to please people so they would buy them. But it was still fun. Until federal regulators moved in to clean up America's polluted air. Among their most important targets was the automobile.

Exhaust-emissions regulations in 1971 were not as choking as they would become, but they had already strangled the six-cylinder Jaguar XKE. Neither in performance nor in appearance was it the thrilling super sports machine of a decade before.

The once-crisp, bright engine had been saddled with anti-smog paraphernalia, and the once-clean, marvelously simple body lines had been sullied with new lights and bumpers also mandated by consumer-protection laws about safety and crash resistance.

Every automaker was having to spend more resources on dealing with newly aroused social consciousness than on traditional automotive engineering. Besides that, roadways were becoming ever more congested, regulated, and policed, thus depriving the keen driver of exercising his cherished pastime.

Both cars and driving just weren't as much fun any more; there was, in fact, an anti-auto lobby gleefully predicting the demise of the private motor vehicle. Even companies such as Jaguar were seeing customers concerned more and more with creature comforts and driving ease, less and less with performance and handling -- with sporty style over sporting substance.

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Jaguar XKE V-12 Engine Origins

It was against this darkening background that Jaguar unrolled the drawings of a V-12 engine that it had designed in the very different times of just a few years before.

V-12 engine in the Jaguar XJ13 midengine test car
The idea behind the V-12 in the Jaguar XKE Series 3
could be traced to this V-12 in the XJ13 test car.

Actually, the thought of someday building a Jaguar V-12 dated back to the early XK years of the late forties and early fifties. The idea finally took substantive form in the mid sixties, when some of the firm's competition-oriented engineers secretly built and tested a sports-racing car that promised to again raise high the Jaguar banner at LeMans.

This was the XJ13, an open two-seater with much of the immortal D-Type in its body and chassis, but powered by a massive 5.0-liter, four-camshaft, 500-horse V-12 mounted behind the cockpit in modern mid-ships configuration. The man primarily responsible for the engine-code-named XJ6, by the way-was Claude Baily, a member of the team that designed Jaguar's XK six.

According to the original thinking, the quad-cam twelve would have been developed and proven in racing, then detuned for docility and longevity as a passenger-car powerplant. A sound plan, as Ferrari, Maserati, and others had shown.

For reasons both political and financial, Jaguar abandoned the racing program, but the initial "competition" engine would serve as the conceptual and experiential basis for a new V-12. However, this second unit was never intended for the race track. It was envisaged strictly as road-car power, primarily for a future range of sedans.

Why a V-12, exactly? Engineer Wally Hassan once explained it in an interview with Motor: "Jaguar have always tried to provide luxury at a reasonable cost. Our problem was how to make the most reliable engine with the power to do the job and a lot of torque and refinement as well. We chose a V-12 formation because it gives perfect balance and, as vibration spells noise, this means a quiet as well as a smooth engine. In addition, the three-plane crankshaft is known to be the best configuration from a torque point of view."

Hassan left unstated the equally important commercial consideration that, at the time, only Ferrari and Lamborghini offered this many cylinders in roadgoing automobiles, albeit in very high-dollar exotics. Jaguar could bring the romantic song of the twelve to a great many more people.

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Jaguar XKE V-12 Engine Design

As finalized, Jaguar's production V-12 was a bulky, beefy thing, big enough to encompass an ultimate displacement of a good 7,000 cc (427 cubic inches). However, to meet the power requirements immediately foreseen, the engineers chose a swept volume of 5,343 cc (326 cubic inches) through a bore and stroke of 90x70 mm (3.54x2.76 inches).

The single-overhead cam V-12 of the Jaguar XKE Series 3.
Where the XKE's 4.2-liter six cruised at 100 mph with
little throttle opening, the Jaguar XKE Series 3 V-12
(above) cantered at 120, and still had power
enough to surge when unreined.

The angle between the two banks of six cylinders was 60 degrees, traditional for a V-12 because it gives even crank throws and thus smoother running. Both the heads and the block were cast in aluminum alloy for light weight -- a savings of 116 pounds over the same design in cast iron.

That weight-savings was known exactly because, concerned about noise, the factory did cast one experimental block in iron. But when installed in a test car, it proved not significantly quieter than the aluminum engine.

Within the block were pistons running in wet iron liners. For strength and, again, smoothest running, the skirts of the crankcase extended well down around the crankshaft, which was made of forged steel and whose main bearings were secured by four-bolt cast-iron caps. To be sure of adequate crankshaft support, seven of those bearings were specified.

The prototype "XJ6" twelve had twin-cam heads in the classic mold of the XK six. But Hassan, a former Jaguar man who'd returned to the company after its purchase of Coventry-Climax, was not impressed with the Baily engine's power output.

Having just spent some years building world championship-winning Formula One engines -- tiny 1.5-liter V-8s producing around 200 horsepower (a startling 133 horsepower /liter), Hassan thought that out of 5.0 liters one should have seen much more than 500.

This was not an especially kind judgment, for Baily and his team really hadn't had much chance to develop their racer. Moreover, compared to the racing Coventry-Climax eight, each of the V-12's pistons had to shoulder almost two-and-a-quarter times as much work.

However, the quad-cam layout did create problems with bulk, weight and cost for passenger-car applications. It also made for a lot of trouble in the mounting of accessories necessary on a street car.

Investigating alternatives through a series of single-cylinder test engines, Hassan decided that the most suitable head design was one with a single camshaft and valves parallel to one another and to their cylinder axis.

Because bore was large relative to displacement, there would be ample valve area for good breathing at the moderate rpm this engine would be turning in its everyday traffic duties. Twin cams and hemispherical combustion chambers simply weren't needed. Not incidentally, using single-cam heads rather than a pair of XK-type twin-cams saved about 44 pounds.

In fact, not even combustion chambers were needed. At least, not in the conventional sense. For reasons connected both with smog control and manufacturing ease, Jaguar's new V-12 cylinder heads were machined completely flat on the bottom, flush with the valve heads. Combustion chambers were formed by depressions cast into the piston crowns.

Such a design, not invented by Jaguar but not common, is known as a Heron head. However, Jaguar's engineers took pains to explain that their version was not a true Heron, because the piston "bowls" were broader and shallower.

These dished pistons were designed to give a compression ratio of 9.0:1 to suit 97-octane gas. Although fuel injection was becoming familiar in the industry, the engine couldn't be made to meet smog levels with such a system, so Jaguar fell back on emission-control Zenith-Stromberg carbs. There were four of these mounted at the ends of long, over-the-top intake manifolds designed to boost low- and mid-range torque.

On the ignition side, though, Jaguar did break new ground with the first production application of a Lucas electronic system called OPUS, originally created for racing cars.

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Jaguar XKE V-12 Horsepower

How much power did the Jaguar XKE Series 3 V-12 engine really make? A precise number is a little hard to pin down.

As finalized for the XKE Series 3, the power rating for European use was 272 horsepower on the DIN scale at 5,850 rpm. That would translate to 282 SAE. However, in U.S. marketing literature, the V-12 was said to deliver 314 horsepower at 6,200.

The signature hood buldge of the Jaguar XKE was retained in the new XKE Series 3.
The signature hood bulge of the Jaguar XKE was
retained, even though it wasn't needed to clear the
new XKE Series 3 V-12 engine.

The tachometer's redline was way up at 6,500, by the way, and the engine could actually turn to 7,840 before the valves started bouncing in their springs. Torque was listed in the same materials as 349 lbs/ft at 3,600, but the European DIN measurement was 304 at 3,800.

These differences can be explained by two factors. First, the American figures were idealized, being derived from dynamometer readings of a test engine unfettered by mufflers, air cleaner, fan, and other accessories.

Second, importers like Jaguar could easily waffle about the potency of their "American versions" because, in 1971, the switch was on from advertising the traditional, but misleading, SAE-gross measurements to more realistic net outputs, and there was some public confusion as to what the conversion factors should be.

There was also this: U.S. emissions standards were then tightening so rapidly, and even inconsistently, that stated outputs could vary a lot from one model year to the next and, sometimes, even within a model year.

This was particularly likely if a manufacturer needed to resort to different tuning to meet the stiffer emissions limits set by the smoggy state of California. We're inclined to believe 1,972 quotations in Road & Track as both plausible and definitive: 250 horsepower at 6,000 and 283 lbs/ft at 3,500, both SAE net and applicable to all 50 states.

But none of this really mattered in the end. Few Jaguar buyers have ever based their purchasing decisions on the precision of engine outputs. The important point was that the XKE Series 3 had more punch than the XKE Series 2, enough to just about bring this much-heavier, much-less-aerodynamic car back to the performance levels of the original XKE.

According to measurements made for this article of display engines at the Jaguar factory museum, the V-12 measured 2-7/8 inches longer than the old inline-six, or 35-7/8 inches from rear of flywheel to nose of crankshaft. Height was actually a quarter-inch less, 26-1/2 from sump to the tops of the induction system; the engine itself, to the tops of the cam covers, was only 22-1/4 inches high.

Of course, overall width was greater, especially when the V -12's sprawling induction system was considered. With this and all the other necessary ancillaries, the engine occupied a "box" measuring 44x39x27 inches.

So it was big -- but not especially heavy. A good deal of arrant nonsense has been perpetrated over the years about the weights of Jaguar engines. Well, they're not made of fluff and foam, but they're not boat-anchors, either.

In The Jaguar Scrapbook, marque historian Philip Porter published a list of weights of various Coventry powerplants "as installed on testbed." These were taken minus fan, air cleaner, clutch, and transmission, and without any fluids, but with flywheel, electrical equipment, and exhaust manifolds.

In this trim, a 3.4-liter XK (for the 340 sedan) weighed 567 pounds, according to Porter. The 3.8, with its added cylinder liners, came to 592, while the 4.2, which had the redesigned block with different bore spacings, scaled 605.

And the 5.3-liter V-12? A mere seven pounds heftier, at 612. With the engine dressed for installation, the factory said its total weight came to 680 pounds.

Granted, that was substantially heavier than a typical small-block Detroit V-8, but let's not forget that the Jaguar design was really a big-block enclosing a relatively small displacement -- and was an inherently much-more-complex, more highly refined design to boot.

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Jaguar XKE Series 3 Design

Fitting the V-12 into the XKE chassis took surprisingly little work. Lengthwise there was no problem; both Series 3 models rode the longer 2+2 wheelbase for reasons other than engine installation.

The magnificient Coventry cat, the Jaguar XKE Series 3 V-12.
Some testers deemed the Jaguar XKE Series 3
"a magnificent engine in an outclassed body,"
but the Coventry cat looked -- and went--
like little else on the road.

However, the quartet of square-section tubes forming the main engine-bay space-frame had to be moved apart by several inches. Also, the top forward frame member was made detachable for ease of engine installation; the powerplant was now dropped in from above whereas the twin-cam six-cylinder had been inserted from below.

There also was some additional bracing and, because it had to be revised anyway to suit the altered frame dimensions, the firewall was beefed up.

While modifying the framework, Jaguar also re-engineered the front suspension, introducing anti-dive geometry to resist forward pitching under hard braking. Track dimensions were wider, the former 50-inch width at each end going up to 54.6 front, 53 rear.

Some of that increase was due to the specification of wider, low-profile tires. Wheel travel was increased for a softer ride. Spring rates were revised upward, front brakes were given ventilated discs, and the rear discs were cooled by new air scoops.

All these changes were necessary because the longer car with its added luxury equipment was heavier. With that and the wider tires, power rack-and-pinion steering was standardized. However, redesigned rubber mounts reduced the rack's former tendency to move sideways, thus cutting play in the steering.

Rubber appeared in torsion-bar and sway-bar mounts for the first time, again to soften the ride. Gas-charged shock absorbers, then in their infancy, were adopted to keep damping consistent as heat built up in the fluid with heavy use. These and numerous other detail changes all added up to a car that really was much newer than it looked.

Having wearied of complaints from taller members of the driving population who couldn't fit in the original XKE, Jaguar dropped the original 96-inch-wheel-base coupe and adapted the convertible bodyshell to the 105-inch span of the closed 2+2.

Even shorter folk who might not need the extra nine inches of cockpit length could appreciate how this made for easier entry/exit and more useful reclining seats.

Also more useful, thanks to the V-12's greater torque, was the optional Borg-Warner three-speed automatic transmission. The well-liked all-synchro manual four-speed remained standard, and was untouched save a larger clutch.

Any negative remarks about handling changes brought on by the long wheelbase were muted by the fact that Jaguar managed to alter the steering system to reduce the turning circle. It went from the very wide 42 feet of the 2+2 chassis to a much more manageable 36.

Still, the sharper steering angles added nearly a full extra turn of the helm, from 2.6 up to 3.5 turns lock-to-lock. One might have expected a quicker ratio in view of the now-standard power assistance. However, the power assist did allow a smaller steering wheel, now 15 inches in diameter and leather-wrapped.

The high-roofed coupe bodywork remained virtually the same, but on the new convertible the rear occasional seats were exchanged for a small-but-useful luggage area. The convertible's doors were obviously longer than before and its windshield shaping somewhat different.

On both models, wider tires required small flares for all wheel openings. Modern air-extractor vents appeared on both the coupe and the convertible's still optional liftoff hardtop to improve cabin ventilation, always an XKE sore point.

Up front was a still-larger "mouth" to admit extra cooling air. The appearance was further aggravated by the first formal grille on an XKE. The broad cross-hatch dental work with a small vertical divider was topped by a Jaguar escutcheon, all rendered in sparkling chrome. Despite the enlarged opening, an additional inlet was added below. Both served a bigger radiator offering 40-percent greater cooling capacity.

Another body change was to the underside at the rear, where a lower line housed a larger gas tank. That addressed a point of criticism on the original XKE by bringing fuel capacity from 17 U.S. gallons to almost 22.

Bumpers were refashioned at both ends, taillamps enlarged, and the standard steel-disc wheels redesigned with circumferential slots and nipple-like hubcaps.

Inside was a noticeable lowering of the floor to improve foot room. This was partly dictated by a transmission tunnel made wider and stronger so as to force the engine safely down and away from occupants in case of a head-on crash.

Despite all these alterations, many of the Series 3's basic body stampings were interchangeable with those of earlier XKEs. Even the hood bulge remained. It wasn't necessary to clear the new engine, but who would dare lose this distinctive and pleasing hallmark?

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Jaguar XKE Series 3 Reviews

This emphasis on retaining the strong Jaguar XKE identity raises some interesting questions. For example, is it possible that the XKE Series 3 might have been better received had it not looked so much like the original? Or if had it been called "F-type;" as widely expected?

Car and Driver tested the 1971 Jaguar XKE Series 3 convertible.
Car and Driver's 1971 Jaguar XKE Series 3
convertible test yielded these numbers:
0-60, 5.5 seconds; quarter-mile, 14.6 at 93;
top speed, 135; price as sampled, $8,809.

As long as it was spending so much money, Leyland-owned Jaguar might well have spent a little more on restyling (to better integrate the headlights, for example). Then the XKE Series 3 V-12, or "V-12E," could have demanded acceptance on its own terms as something new.

Instead, the first impression for some people was that the poor old XKE had somehow been made too long and heavy and soft; and besides, there was something wrong with its nose. Nevertheless, the XKE Series 3 really was a new car in most respects.

"Perhaps a little naively," confessed Roger Bell in his April 3, 1971, Motor road test, "all we expected to try was a new engine. What in fact we drove was a new car -- not a yowling, aggressive Ferrari-like machine with which, perhaps, most people associate a V12 engine, but a very smooth, quiet and refined grand touring sports car."

In several respects, Bell's prior expectations produced "disappointment." That was the actual word, an extraordinary word to find in a British review of a high-end British car.

"It is only at the top end of the rev range that you really begin to hear that beautifully distinctive and busy V12 purr," he observed. "At lower speeds exhaust noise is well subdued -- perhaps too much so for sporting cars. Inevitably, there will be further disappointment that the car itself looks much the same as it did 10 years ago ... We ourselves are disappointed that certain detail things have not been improved-such as the switchgear."

Bell did find several things to laud. The V-12, especially. "For its flexibility low down -- by no means a weak point of the old XK [six] -- and for its smoothness at the top of the rev band, the new engine is outstanding, altogether in a different class. It will pull strongly in top gear from under 500 rpm with an uncanny absence of vibration ... Its ability to rev smoothly and willingly up to 6,500 rpm is perhaps of greater significance, at least in the XKE, for the [4.2-liter] XK begins to feel rough at 4,500 rpm.

"On twisty secondary roads where all good sports cars should excel, the engine's smoothness and eagerness encourage far more use of the lower gears than before."

Bell also liked the ride, "excellent by any standards," and the handling and roadholding; he called the general manners "impeccable." The power steering, though, was "rather too light" for his taste.

Motor Sport's race reporter, the eminent Denis Jenkinson, was able to assess the new design on the basis of his own 150,000 high-speed miles in two examples of the six-cylinder model. He immediately disliked the driver's seat cushion, calling it too high and too flat for him. And he detested the automatic transmission fitted to one of the two Series 3s he sampled.

Nor did "Jenks" approve of the way the big radiator opening had "a decorative bird-cage grille stuck up its nose." From a mechanical standpoint, he was surprised, after years of intimate experience with high-performance V-12 engines from other manufacturers, that Jaguar's was so smooth and silent -- enough that he wasn't always sure it was running.

And at first, at low speeds, Jenkinson didn't seem to see any advantage in having twice the number of pistons.

"Throughout the whole afternoon I spent driving the two 12-cylinder 'E'-types, I found myself continually commenting that I would never know there was a V12 under the bonnet, especially when cruising about in a normal, leisurely 'seven-league-boot' fashion, but now and then there would be occasion to pull out and squirt past some traffic, and in the 70-110 m.p.h. range it really did come into its own.

"My reflexes and judgement being well attuned to 'E'-type performance in this speed range, I soon found that the V12 did not need anything like the time and space I was subconsciously allowing for overtaking, which made me realize how rapidly it was accelerating, making it an even safer and more long-legged car than the old six-cylinder."

At the end of his rapid afternoon, Jenks slipped back into his own XKE Series 2, and " ... as I motored off, my smooth, silent, silky, six-cylinder engine seemed as rough as the proverbial bear's hindquarters, and I realized that Jaguars [sic] have made an impressive step forward in refinement, which is so encouraging in these days of glorification of the cheap and shoddy."

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Jaguar XKE Series 3 Performance


The XKE Series 3 V-12's performance is nicely described though the experiences of celebrated British auto journalist Denis Jenkinson. He wrote about testing XKE Series 3 V-12 for a full week because he had been thinking of trading in his XKE Series 2 for one. Why he decided against it is interesting.

The Jaguar XKE Series 3 V-12 coupe retained its rear +2 seating, as well as its high roofline.
©2007 Jaguar Cars and Wieck Media Services, Inc.
This is the very last Jaguar XKE built. It's a
1975 XKE Series 3 V-12 convertible fitted with
an optional factory lift-off hardtop.

For all normal motoring purposes I could not see that the V12 engine gave any particular advantage over the six-cylinder apart from incredible smoothness and flexibility," Jenkinson observed in Jaguar E Type, a book about his experiences with the model.

"Obviously it had a lot more power, and it did everything the 4.2 did but at 20 mph higher speed. Where the 4.2 would cruise at 100 mph with little or no throttle opening, the V12 cruised at 120 mph with the foot eased right back, but at the expense of 15 mpg against 21 mpg [12.5 versus 17.5 U.S.]. The acceleration of the 4.2 at 100 mph, for instant overtaking or getting ahead of an impending situation, was repeated by the V12 at 120 mph, though maximum speed was no better than [that of] the 3.8-liter E type.

"My eyesight, judgement and reflexes could not really cope with these increasing speeds as a continual way of motoring. I could see no justification for a V12 for my purposes, even forgetting laws and restrictions that were gathering fast in all directions."

Those new limitations of the 1970s, he sorrowed, had made Europe "no longer the happy care-free motoring paradise it had been" in the 1950s and 1960s.

Besides that, Jenkinson went on, the power of the new V-12 had outstripped the basic XKE chassis concept. Even with the Series 3's better tires, suspension, and brakes, "it was all too easy to run out of roadholding, steering and braking ability if you gave the 5.3 liters their freedom. The days of the E type were numbered..."

That sad fact was brought home forcefully a year later when Jenks made a trial run in a prototype XJ12, the running mate to Jaguar's new-generation XJ6 sedan powered by the selfsame 5.3-liter engine instead of the venerable XK six.

"This ... proved to be a giant of a car," Jenks wrote, "with road holding and handling up to using the full potential of the V12 engine. I soon realized that the E type era was over, for on a cross-country run you would have been hard pressed to have kept that big saloon in sight with an E type."

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Jaguar XKE Series 3 in America

Even to Americans who had seldom experienced a "happy care-free motoring paradise," the XKE Series 3 seemed outdated and inadequate.

Road & Track subtitled its October 1972 XKE Series 3 convertible evaluation with this stark critique: "A magnificent engine in an outclassed body."

The Jaguar XKE Series 3 V-12 had better leg room with a 105-inch wheelbase span.
Big rubber bumper guards needed to meet U.S.
impact standards helped identify American-market
Jaguar XKE Series 3 V-12s.

What it found wrong with the latest XKE included these complaints: "...overall design lacks the sleek appeal of the original ... ventilation system is antiquated and the controls laughable ... no place for the driver to rest his left foot ... clutch effort is quite high so [traffic driving] is more a chore than a pleasure ... Seating is another area in which the Jaguar falls behind the times."

R&T also repeated that "reliability has never been a strong point of any Jaguar we have tested and this XKE was no exception." The actual troubles came to no more than a worn alternator drive belt, but the magazine's own wariness of Jags in general paralleled that of its readers as revealed in surveys.

However, the Road & Track crew found much to like about the twelve-cylinder car: "Overall the XKE is an easy car to drive and is most at home when driven hard and fast," they reported.

The new leather-wrapped steering wheel earned good marks for its feel and adjustability -- it had three inches of travel up and down its column and also retained the old XKE virtue of being adjustable for rake, although a wrench was still needed to take advantage of that.

The brakes rated a "very good," the manual gearbox once again won high praise, and the ride comfort and the convertible's body rigidity on rough roads were both judged very good.

Although the tires themselves didn't stick well at all -- R&T said that the contemporary XJ6 sedan cornered faster on the skidpad despite being several hundred pounds heavier -- Series 3 handling was found "neutral under all conditions except for extremely heavy applications of power. On such occasions the tail comes out gently and predictably."

There was quite a pronounced torque-veer, however: When the engine was pulling hard, the car swerved to the left, then darted back to the right when the driver's foot lifted.

Some other contemporary tests mentioned the same phenomenon, by the way, but it should be noted that others made a point of saying their test cars showed no trace of such behavior; perhaps something to do with the condition of the rubber mounts in the rear suspension subframe, or in the way individual vehicles had been assembled.

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Jaguar XKE Series 3 Retires

There was plenty of criticism of the Jaguar XKE Series 3 styling, cabin layout, and reliability. And plenty of it was justified. But the V-12 engine seemed a thing apart from the car, a wondrous package of smooth power just as that was a fast-diminishing quality in the world of early 1970s motoring.

The Jaguar E-Type as Group 44's SCCA B-Production champ in 1975.
The Jaguar XKE's last hurrah came in racing, as
Group 44's SCCA B-Production champ in 1975.

Road & Track, for example, pronounced the 5.3-liter V-12 "a sheer delight, by itself almost worth the price of admission, and to some extent it atones for the sins of the outdated car.

"The V-12 is a lovely piece of machinery, lovely to listen to and lovely to behold. The exhaust has that hurried sound characteristic of a multiple-cylinder engine where the many explosions per revolution make it sound as if it's running faster than an engine with fewer cylinders. The idle is smooth and quiet with none of the mechanical busyness one normally experiences from the likes of a Ferrari or Lamborghini V-12. And the smoothness lingers throughout the rpm range...With the top down one becomes more aware of the nature of the beast lurking beneath that long bulging hood. Mechanical noise slips over and around the windshield and combines with the exhaust note to surround the occupants with sweet and sensuous sounds."

At the curb, R&T's test convertible tickled the scales at 3,380 pounds. That went up to 3,680 "as tested" (driver and test equipment aboard), with a percentage distribution front-to-rear of 53/47.

On the U.S. axle ratio of 3.54:1, the time taken to 60 mph was 7.4 seconds, the quarter-mile came up in 15.4 at 93 mph, and top speed was calculated to be 135 mph at 6,000 rpm.

Car and Driver, testing a similar Series 3 convertible, confirmed that top speed exactly, though it was "observed." However, acceleration was far better: The magazine clocked the quarter-mile in 14.6 at 97 and 0-60 mph in a resounding 5.5 seconds.

After a drive right across the United States, some of it at high speeds in then-unlimited Nevada, Road & Track's fuel consumption worked out to 14.5 mpg (Car and Driver's ranged from 11 to 14). Base price of this 1972 open car was $7,599, but air conditioning, wire wheels, and stereo raised the tab to $8,809.

In summarizing the Series 3, R&T defended its numerous criticisms this way: "We've been harsh on the car, but we believe justifiably so. When the same manufacturer can produce such an outstanding car as the XJ6, it not only spoils us for anything he produces thereafter, but makes it exceedingly difficult for us to justify the existence of a car that is not as excellent."

Sadly, as part of the increasingly troubled British Leyland, Jaguar could only let the XKE slip further. Tightening U.S. emissions standards prompted compression to be eased as the years passed, and Washington's mandate that bumpers be able to survive five-mph shunts prompted ludicrous rubber-block bumperettes for 1973-1974.

By that time, only the convertible could find buyers, and demand for that was tailing off. Production was apparently shut down around the end of 1974, although Jaguar kept the fact quiet until early 1975 so as not to complicate clearing the large stocks still on hand.

The very last XKE Series 3, a convertible appropriately finished in black, rolled down the Browns Lane assembly line and straight into the factory museum. It was the 15,287th Series 3, and the end of a proud XKE line that reached total production of 72,520.

Before concluding the generally dim XKE Series 3 V-12 story, it is pleasant to record one brief shining moment. "Camelot" in this case was the state of Virginia and the headquarters of a racing team called Group 44.

Sponsored by Jaguar and headed by Bob Tullius and Brian Fuerstenau, it entered race-prepped V-12 roadsters in SCCA B-Production events during the summer of 1974 -- ironically, just as XKE production was winding down.

Very competitive that first year, driver Tullius just missed the national title, but came back to win it at the end of 1975. It was a grand success in the glorious Jaguar tradition, but also one that reinforced the reputation of the crisis-wracked conglomerate that owned the marque: It came too late to do any good. Jaguar's sun, it seemed, was sinking fast.

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  • New Jaguars: Reviews, ratings, prices, and specifications on the current Jaguar lineup from the auto editors of Consumer Guide.
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1971-1975 Jaguar XKE Series 3 Specifications

The Jaguar XKE Series 3 V-12 received plenty of criticism for an outdated basic design, but no one could deny the Coventry cat's magnificent V-12 engine. Jaguar sent the beloved XKE out on a note that sounded sour then, but rings pretty sweet today.

Jaguar XKE Series 3 V-12 Specifications

Years produced
1971-1975
Number built
15,290
ConfigurationFront engine; two-seat and 2+2
Body style
Convertible, 2+2 coupe
Suspension, front
Independent with torsion bars
Suspension, rear
Independent with four coil springs
Wheelbase (inches)
105
Track, front (inches)
54.5
Track, rear (inches)
53
Overall length (inches)
184

Jaguar XKE Series 3 V-12 Engines

EngineV-12
Type
60-deg. V-12 aluminum block and heads, one overhead camshaft per head, two valves per cylinder
Displacement, liters/cc
5.3/5343
Maximum horsepower
295

Jaguar XKE Series 3 V-12 Performance

Best 0-60 mph (seconds)
6.4
Best top speed (mph)
146

For more on Jaguar and other great cars, see:

  • Jaguar Cars: Check out more information on the great sporting cars.
  • How Sports Cars Work: Get the lowdown on hundreds of fantastic sports cars from the 1940s to today.
  • Classic Cars: Learn about the world's most coveted automobiles in these illustrated profiles.
  • Ferrari: Learn about every significant Ferrari road car and racing car.
  • New Jaguars: Reviews, ratings, prices, and specifications on the current Jaguar lineup from the auto editors of Consumer Guide.
  • Used Jaguars: Reviews, recalls, trouble spots, and more on pre-owned Jaguars starting with the 1990 model year. From the auto editors of Consumer Guide.