15-17 - VdP EFi.qxd

When ‘S’ was best
Was the manual-transmission 3500S really the most
desirable P6 of them all? James Taylor – who owned one
back in the 1980s – assesses the case for and against
R
ight from the start the
Buick V8 engine was seen
as the means of injecting
some much-needed performance
into the Rover range. The initial
impetus for its purchase had
come from North America, where
Bruce McWilliams, who ran the
US and Canadian import
business, had recognised early
on that the Rovers of the early
1960s were just too slow and
staid to attract many US
customers. Once he had
persuaded managing director
William Martin-Hurst of his case,
and once Martin-Hurst had found
the engine and done the deal
with General Motors, the next
thing was to integrate the new
engine into Rover’s future
product plans.
It wasn’t quite as simple as it
might have seemed. For a start,
the engine delivered rather more
torque than any existing Rover
gearbox could handle. This
meant that the engineering
resources would have to be
found to develop one, unless a
suitable unit could be bought in
from outside the company. The
next big issue was that it was
The first P6 models to have the V8 engine were put on the market in 1968, and were available only with Borg
Warner automatic transmission. Styling was much plainer than on the later 3500S cars
more important for Rover to use
the engine to stop its ageing P5
3.0-litre luxury saloon losing
sales on the home market rather
than to go after incremental
sales in the still developing
North American market.
All of this led to a compromise
that turned out to be a happy
one for the P5. Since this was a
luxury car, and because most of
the people who bought it chose
automatic transmission – and
not least because the latest
Borg Warner Type 35 automatic
was just about capable of
handling the torque of the V8 –
the solution was to mate V8
with Borg Warner automatic and
get the re-engined car out into
the showrooms as quickly as
they possibly could.
Inevitably the rush to do this
diverted some resources from
developing the high-performance
V8-engined P6 that McWilliams
so badly wanted for North
America, and which Martin-Hurst
recognised would do Rover a
power of good almost
everywhere else. The fact that
the solution worked so well also
meant that only a few people
complained when the same
powertrain was fitted to the P6
to deliver the P6B 3500 in April
1968 – making this the first
Rover, incidentally, to be
introduced after the creation of
the ill-fated British Leyland.
There were three
transmission-development cars
among the batch of 25
V8-powered P6 prototypes
built in 1966, and former
engine-test engineer Brian Terry
remembered them being
registered JXC 801D, JXC 810D,
and JXC 817D. JXC 801D may
have been used for
development with the
automatic gearbox, so the other
two would have been the first
manual-gearbox P6s with the V8
engine. Probably neither was
ever tried with the 2000’s
four-speed gearbox, because
on-paper calculations alone
would have made fairly clear
what the result would be.
Instead both were fitted with a
five-speed manual gearbox
made by ZF in Germany. This had
already been tried out in the sixcylinder P7 prototypes, and was
probably the same gearbox that
BMW had just begun to use in
its high-performance 1800TI/SA
sports saloons, and would go on
to use in other models later.
For Rover the main attraction
of this transmission was
probably its torque capacity
rather than its five forward
speeds. Its gear ratios were
arranged to give smaller
between-the-gears steps than a
four-speed gearbox, and with a
direct-drive fifth gear rather
than an overdrive type. But it
had been designed as a sports
gearbox – five-speed types were
extremely rare in the mid-1960s,
and invariably associated with
sporting machinery such as the
Porsche 911 – and Rover decided
that it was just too unrefined for
the typical Rover owner.
So there was a change of plan.
The problem was handed back
to Frank Shaw’s transmission
engineers at Solihull, who found
themselves under some
pressure to come up with the
goods. They were already
working on a new four-speed
gearbox to go behind the V8
engine, but this had been
The P6’s ‘Series II’ styling was accompanied (on the 3500S) by distinctive
spoked wheel trims and a vinyl roof. It was all very much of the 1970s!
specifically conceived as a
Land Rover gearbox (it would
eventually go into the Range
Rover and the 101 Forward
Control) with an integral
two-speed transfer gearbox.
Clearly it would not suit the
V8-powered P6, but resources
were limited, and there could be
no question of designing
another new manual gearbox in
the timescale that management
wanted. The solution was simply
to uprate the existing fourspeed gearbox from the Rover
2000 in order to withstand the
torque of the V8.
In fact, the gearbox was
heavily redesigned, even though
it was equally heavily based on
the existing four-speeder. A new
and stronger outer casing
allowed for more than twice the
oil capacity of the 2000’s
gearbox, and fins on the outside
provided a modest degree of
additional cooling. The rear of
the layshaft was modified to
drive an oil pump so that the
gears and bearings were always
under positive lubrication
(rather than by splash alone)
when the car was moving.
Characteristic of the early 3500S was the box-pleated
upholstery. The black interior and yellow exterior were
again entirely typical of 1970s’ tastes
The visual balance of power and sophistication seemed to work exceptionally well on the 3500S
The layshaft was given taperroller bearings in place of the
original needle-roller type, and
the gears were shot-peened. By
about 1970 the new gearbox
was ready to do the job. That it
could only just do that job was
something that – to the
transmission team’s credit –
would not become apparent
until many years later.
The manual-transmission
V8-engined P6 was launched in
October 1971 as the 3500S –
a name which would forever
cause confusion with the by
then extinct North American
3500S automatic – and
immediately caused a sensation.
Here was a car which embodied
all the expected Rover qualities
(give or take things like leather
upholstery and the traditional
Rover discretion), and to them
added (for the time, and
especially for a Rover) high
performance. And it really was
high performance: 0–60mph in
9.1 seconds was strong stuff for
a four-door saloon in those now
far-off days, knocking about 1.5
seconds off the time of the
automatic car, and completely
transforming its character.
That transformation was
reflected in the car’s trim and
equipment. Rover reasoned that
buyers would be attracted to
the 3500S by its sporting
character, and probably
wouldn’t be very interested in
leather upholstery. So the seats
of the 3500S were covered with
Ambla – a type of vinyl that bore
a passing resemblance to
leather – and they also had a
distinctive box-pleated design
which had been used in the
North American 3500S, but
which hadn’t been seen before
outside the USA and Canada.
Externally a vinyl roof and rear
quarter pillars made the car
look more sporty, and were a
nod to one of the latest
automotive fashions, while the
five-spoke stainless-steel wheel
trims developed for the North
American V8 car added yet
another sporty touch. Sills were
painted to match the vinyl roof,
which meant that while most
were Satin Black, some were in
a very attractive colour called
Huntsman Brown.
In my book on the P6 range,
Rover P6, 1963–1977, I called
the manual-transmission 3500S
‘the masterpiece of the P6
range’, which was a view that
the press took as soon as the
car was released. In its issue
dated 16th October 1971, Motor
magazine said it all in one
somewhat unwieldy sentence.
Its testers thought that the car
had an ‘unrivalled combination
of high performance and
reasonable economy, good
handling and roadholding, an
excellent ride, refinement with
much luxury and, perhaps most
important of all, quality’. No
matter that the performance
gains over the automatic 3500
were ‘rather academic and only
apparent in the upper speed
ranges’. They liked it.
Britain’s other weekly
motoring magazine of the time,
Autocar, was equally
enthusiastic. Although it was no
fan of the new gearbox,
complaining of gear whine in the
indirect ratios, and a slow
change action, it was none the
less delighted by the car’s
‘excellent mid-range
performance’. The 3500S was
‘more than a match for its
Rear badging made very clear what the car was when it passed you...
competitors, both British and
foreign’, it said, and added that
its features combined to
‘surpass all expectations’.
The 3500S certainly was some
car. It quickly became a
favourite with police forces in
Britain, who from March 1973
were offered a special heavyduty version of the four-speed
gearbox. This had a stronger
layshaft cluster and stronger
intermediate gears, which made
it rather tougher than the
standard production type, but
also rather noisier. The police
used the 3500S especially for
motorway-patrol duties, where
its high performance could be
an important factor in getting a
patrol team to the scene of an
incident before it turned into a
crisis with several miles of
tailback. The popular image of
the 3500S ‘jam sandwich’ is of
the car being used for highspeed pursuits on the
motorways, but such chases
were always relatively rare.
Sales were strong, too,
although the 3500S was never
as popular as the automatictransmission 3500. Rover
owners seem to have liked their
luxuries, and voted in the main
for the Borg Warner-equipped
car. They liked the extra
acceleration of the V8, but not
if they had to change gear
themselves to achieve it! That
same conservative attitude
even affected the further
development of the 3500S. It
quickly became clear that
Rover’s marketing people had
been wrong to assume that the
buyers of sporting saloons
wouldn’t be interested in
leather upholstery, and so from
January 1972 leather upholstery
became available. In order to
keep the base price of the
3500S competitive, however, it
was offered as an extra-cost
option. Many took the bait.
By the time the car went out
of production in 1976 to make
way for the new SD1 3500, it
was still widely respected as a
high-performance saloon, and
was still a hot property on the
second-hand market. It was only
after the superior performance
and interior space of the SD1
had made their mark that prices
began to drop. Then, as the cars
became affordable to less
wealthy buyers, it suffered the
same fate as had the Jaguar
Mark 2 some years earlier. Many
examples of the 3500S fell into
the hands of people who
wanted the high performance
but weren’t prepared to pay for
the maintenance. A lot of cars
were driven into the ground in
the late 1970s and early 1980s –
and that was when the gearbox
troubles began to show up.
The problems tended to come
about either because of oil leaks
that went unattended (Rover
recommended that the level
was checked every 6000 miles)
and/or because the wrong oil
had been used (the company
recommended a 20W engine oil
rather than conventional
gearbox oil, which is usually
thinner). Hard use by drivers
with no mechanical sympathy
did the rest. Gearboxes became
noisy, teeth became chipped,
third gear would jump out of
mesh on the over-run, and
things went from bad to worse.
The best solution, some
owners thought, was to replace
an ailing gearbox with the latest
Key 3500S production changes
Suffix ‘A’ models were built from the start of production in summer 1971 until September 1972.
In approximately January 1972 inertia-reel seat-belts became standard, ‘teardrop’ headrests replaced
the so-called ‘ET’ type (although headrests were still optional at this stage), and leather upholstery
to the 3500 pattern (ie not box-pleated) became an option
Suffix ‘B’ models were built between October 1972 and January 1973. The engines also became
suffix ‘B’ types, now with lip-type crankshaft rear oil seals, and the engine number next to the
dipstick. A revised steering-column lock lost the second inhibition feature. Through-flow ventilation
was deleted from the rear body pillars (although it had gone from the final suffix ‘A’ models, as well)
Suffix ‘C’ models were built between February 1973 and September 1973. The original machinesensed 11ACR alternator was replaced by a battery-sensed 18ACR type. The hazard lights lost their
separate fuse, and the fuse for the HRW was now in the main fuse box. The original hooked, hardplastic knobs for the choke and petrol reserve were replaced by round knobs in a softer material.
From April 1973 Champion L92Y spark plugs replaced the original L87Y type to reduce misfiring.
In July 1973 Dunlop Denovo run-flat tyres became optional for cars with power-assisted steering
Suffix ‘D’ models were built between October 1974 and December 1976. These had a lowercompression engine (9.25:1 instead of 10.5:1) to cope with the phasing-out of 100-octane petrol. A
driver’s door mirror became standard, and a passenger’s door mirror was optional. Sundym glass and
headrests became standard for the home market, and the heated rear window was fitted for most
markets. The five-spoke wheel trims were replaced by the push-fit type used on other P6s. The
front-seat backrests were reshaped to give more rear legroom, and Ambla upholstery was deleted,
while box-pleated and ventilated leather became optional. A tufted carpet material and a lightercoloured ‘wood’ trim were used. A longer gear lever was fitted, together with a safety-stem rear-view
mirror, and a mirror on the passenger’s sunvisor. The parking-light position was deleted to meet new
legislation. Lucas Square 8 fog-lights replaced the earlier Cibié option, and black rubber floor mats
replaced the earlier link and charcoal-grey types. In approximately October 1974 the push-pull switch
for the heated rear window was replaced by a rocker type
LT77 five-speed type from the
Rover SD1 – and as SD1s began
to succumb to their own many
problems during the early
1980s, so such transmissions
became more plentiful on the
second-hand market. It was a
reasonably straightforward
conversion, but inevitably many
owners neglected to tidy up the
console area around the
relocated gear lever, leaving the
conversion looking somewhat
makeshift. The five-speed
How many were made?
Some 17,721 3500S models were built, mostly for the UK market
Fast and stylish, 3500S was very much a car to be seen in during the 1970s
Home-market cars
48100001A to 48111747D (June 1971–December 1974)
Between January 1975 and December 1976 cars were numbered
within a combined sequence (see below)
conversion also delivered a
3500S with very strong
acceleration, much more refined
high-speed cruising, and better
fuel consumption.
I had a 3500S in the 1980s, and
I wouldn’t be at all surprised to
find HOV 310N still around
today. It should be, after all the
rebuilding I had done on the
underbody! It was a superb car
to drive, with shove-in-the-back
acceleration in every gear, and
its own endearing transmission
whine in the intermediates. Fuel
economy wasn’t too bad, either,
and it would usually achieve at
least 20mpg even when I was
trying hard. It eventually went in
favour of an SD1 2600S manual
RHD export cars
48200001A to 48201097D (November 1971–December 1974)
One car was not built, making a total of 1096. The combined
sequence was used from January 1975 to December 1976
LHD cars
48400001A to 48402275D (August 1971–December 1974)
The combined sequence was used from January 1975 to
December 1976
In the combined sequence serial numbers ran from 13000 to
15002, with prefixes 481-, 482-, or 484- as appropriate. Within that
range, 106 cars were not built, making the total 1897
(which was an exceptionally
good car, but that’s another
story), and it was a real wrench
eventually to part with it.
Would I have another? Yes, I
would, but circumstances these
days are very different. Back
then the 3500S was a wholly
practical everyday car for me.
These days, with young children
to cart around everywhere, it’s
not a very sensible proposition
for that kind of use, and I’d have
to think of it as a weekend
warrior. Then there’s the issue
of where on earth I’d put it… But
then we all face that kind of
problem from time to time, and
we usually manage to get
around it somehow, don’t we? ■