This article was first published in 2004.
One of the most unsung of exotic sports cars must surely be the Jaguar XJ-SC V12.
A sweet V12 engine, good aerodynamics, a 230+ km/h top-end and Jaguar prestige
combine to create a package that we reckon deserves more attention.
Time for a quick background check.
The Jaguar XJ-S hardtop coupe debuted in 1975 as the successor to the famous
E-Type. The new XJ-S was a relatively large vehicle with more focus on space and
practicality and was pitched squarely at the lucrative American market. At the
time of release, however, the XJ-S was much maligned by the media – especially
for its dubious build quality in the early years.
Running changes were made to improve various aspects of the XJ-S, but the
biggest change came in the early ‘80s in the wake of the OPEC fuel crisis. In 1980, Jaguar enlisted the services of engineering guru
Michael May (who was widely recognised for his previous work with Porsche).
Michael headed a team that sought to improve the existing 5.3-litre V12’s poor
fuel consumption. This involved redesigning the heads (with particular
improvements in combustion swirl) and lifting the compression ratio to a massive
12.5:1. (Leaded fuel had a very high octane rating back then!) It was 1982 when
these revised V12s – dubbed HE (High Efficiency) – were released onto the
In 1984/1985, Jaguar then expanded the XJ-S range with a cabriolet version.
This unusual machine features two lift-off solid roof panels and the option of a
folding rear hood or fixed rear window. This was the first open-top Jag since
the E-Type Roadster, which died in 1974. Interestingly, safety regulations
limited the cabriolet to a seating capacity of just two – pretty abysmal
considering the overall size of the car! Not surprisingly, the cabriolet model
was axed during 1988 when it was replaced by the ‘proper’ convertible.
The XJ-SC convertible was first
previewed at the 1988 Geneva motorshow, where it
attracted plenty of attention. It was the vehicle to challenge the existing
Mercedes-Benz SL and Porsche 911. Like the discontinued cabriolet, the XJ
convertible was based on the same underpinnings as the XJ-S but structural
stiffening was added to the A-pillars, sills, underfloor and bulkhead. This gave more torsional stiffness than the cabriolet. The frameless doors that
were introduced were also extensively tested for strength and durability.
The XJ-SC convertible’s
soft-top hood is manually released by twin latches on the windscreen header rail
but it has an automated retraction mechanism activated by a switch in the
console. The hood motor and
hydraulic pump are hidden in one side of the storage compartment. Interestingly,
the rear window is made of glass and comes with an electric demister – no cheap,
plastic-type rear window here!
Under the skin, the suspension
remained largely the same as the XJ-S. That means the front uses double
wishbones, coil springs and an anti-roll bar. The rear suspension is fully
independent with lower transverse wishbones and driveshafts acting as upper
links. Drive is to the rear wheels via a limited slip centre differential.
A four-wheel-disc brake system
came standard along with ABS control incorporating a new yaw sensor. The
rack-and-pinion steering came power assisted.
Many of the XJ-SC’s body parts
are interchangeable with the XJ-S coupe, but no less than one-third of the
pressings were new or modified. There were lots of subtle changes, such as the
adoption of one-piece door windows to reduce weight and aid aerodynamics. Still,
total weight of the XJ-SC was about 100kg up on the XJ-S – the ragtop (with its
added chassis stiffening and mechanical roof mechanism) weighed a substantial
1900kg. The XJ convertible also has an aerodynamic 0.39Cd versus the hardtop
Standard interior features of
this fully-optioned cat includes an adjustable reach steering column, cruise
control, central locking, electric windows, electric aerial, trip computer, air
conditioning, heated front seats with electric lumbar adjust and a
leather/walnut veneer trim. It’s a very comfortable place to be – as you’d
March 1988, the XJ-SC was one of the fastest and most refined open-top cars in
the world. Under the bonnet was the 60-degree 5.3-litre V12 derived from the
E-Type. Using a 90mm bore and 70mm stroke, the SOHC, 2-valve-per-cylinder engine
(in HE-spec) uses a 12.5:1 compression ratio and Lucas-enhanced electronic fuel
injection. The engine features all-alloy construction in an attempt to minimise
weight. Depending on market, max power is 217kW at 5500 rpm. The Australian
version – with a low 11.5:1 compression ratio for unleaded fuel and cat-type
exhaust – made just 195kW at 5250 rpm with up to 377Nm of torque.
Equipped with the standard
3-speed auto (which we believe is a GM Turbo 400) the 217kW-spec XJ-SC 5.3-litre
V12 is claimed to accelerate from standstill to 60 mph (96 km/h) in 7.9-seconds.
Top speed is of this model is also 241 km/h - almost 2 km/h slower than claimed
for the coupe stablemate. The 195kW Australian version, on the other hand,
accelerates to 100 km/h in the low 9s and peaks at a shade over 230 km/h.
And then – just when you thought this was one quick convertible – along came
In late 1993, the faithful 5.3-litre V12 was stroked to a massive 6.0-litres
using a 78.5mm throw crankshaft. Amongst several other engineering changes, the
stroked V12 was now good for 234kW at 5400 rpm together with 463Nm of torque at
3650 rpm. (Note that this engine was also shared with the XJ-S coupe and XJ-12).
A 4-speed auto was fitted as standard to the 6.0-litre convertible. Not
surprisingly, the 6.0-litre XJ-SC can accelerate to 100 km/h in the mid 7s and
run to around 250 km/h. Impressive stuff!
the original 5.3-litre XJ-SC was updated with a 4-speed auto in 1993 but was
discontinued during 1994. With the big 6.0-litre V12 having established itself
as the gun performer of the range, a more affordable 4.0-litre straight-six
XJ-SC was phased in during 1992. Sales were not strong, however, so the
6.0-litre XJ-SC was axed in 1995 and the 4.0-litre model lived only until the
next year. The entire XJ-S series was replaced in 1996.
A Lightly Tweaked Example...
The XJ-SC seen in these pics was recently purchased by David Lawrie of
Australia. David tells us, “I’ve always enjoyed
motorbikes and cars and, after I sold my Harley Davidson, my wife suggested we
buy a convertible – something big enough that the two of us and our three kids
Although its history is a little sketchy, this car has recently been treated
to a minor body restoration including a new coat of gunmetal grey paint. The
marque’s linearity can also be seen in the E-Type style bonnet vents that have
been added. US-spec dual-lens headlights, fog-lights and a rear spoiler were
also fitted. All work was done by the previous owner.
Under the bonnet there’s the big 6.0-litre V12 engine. Power has been lifted
with the change to a twin 2 ¼-inch stainless system and MoTEC management system.
A Crane Fireball ignition booster is also installed. Interestingly, one of those
damn-near unbreakable Supra 5-speed gearboxes has also been fitted behind the
V12 – rest assured there’s always plenty of torque on tap to pull any gear!
We had a chance to drive the
vehicle and can vouch that it’s a very refined, sweet vehicle with ample
on-demand performance. The sound of those twelve cylinders firing is also pretty
rousing when you’ve got the roof down!
Suspension-wise, the car has been brought down a few inches and has received
the usual bush and shock-related maintenance work. The guards are capably filled
by PCW polished 5-spoke 18s wearing 245 and 255 width front and rear Kumhos.
Inside, the previous owner opted to rejuvenate the standard leather trim and
has installed an up-to-date Alpine CD/tuner sound system. A small diameter
sports steering wheel adds to the agile feel of this big cat.
David enthuses, “We’ve owned the car for only a couple of months but already
the whole family loves it. It’s very smooth and great to drive – in fact, my
wife loves to take it out and take the kids for a run along the coast.”
Sounds like this cat has found a loving new family. Maybe we should all look
into adopting a pre-loved cat.