of the Rover P4
in celebration of its 50th Anniversary 1999
Editor Kevin Philips
The all-new post war Rover finally
materialised in 1949, designated P4. This model represented a new departure
from traditional Rover design with the bonnet, wings and body no longer being
considered separate entities. It consisted of a full-width body shell with
straight sides and contour lines pressed into the panels. At the rear, the
boot balanced the bonnet to give the new look "going both ways"
appearance, the new model being loosely based on the 1947 American Studebaker.
The new car appeared in September
1949, its new and curious frontal aspect causing many a broken heart among
devotees of the "classic" Rover style exemplified by the P3's and
the models of the later 1930's. The P4 however was quite up-to-the-minute
in styling and a car that was to create a brilliant future for the Rover Company.
The P4's chassis was a development
from that of the P3 but with a fu]llength frame upswept over the rear axle.
The P3's independent front suspension in its final form was retained at the
front while the familiar semi-ecliptic springs took care of the rear. The
steering was Burman recirculating ball-type, also from the P3. In these essentials,
the P4 chassis remained unchanged for the full 15 years of its production
The first P4 was the Rover 75,
sporting a six-cylinder engine of 2103 cc with a one-piece lightweight alurmmum
cylinder head and manifold, chromium-plated cylinder bores and an external
wipac oil filtration system. Twin SU carburetors were fitted and an oil bath
air cleaner, the engine now giving a slight increase in power, plus greater
flexibility through increased torque compared to the power plant originally
fitted to the P3.
The 75 was joined in September
1953 by the four cylinder "60", developing 60 BHP from a 1997cc
spread-bore engine and the six cylinder "90" developing 90 BHP from
2638cc also in a spread-bore engine. Both engines used a single SU carburetor,
the 60 breathing through a conventional oil-wetted gauze air cleaner, while
the 90 (and export 60's) sported a Vokes paper-element air cleaner. The 90's
compression ratio was raised slightly in 1954 and again in 1955 to give it
93 BHP, which was retained until the end of its production rim in 1959.
In September 1955 for the 1956
model year, the "75" also received a spread-bore engine. This new
engine developed 80 BHP from 2230cc and ran a single SU carburetor and Vokes
paper element air cleaner. Export models retained the oil bath air cleaner.
The spread-bore engine evolved due to the number of changes required to the
basic inlet over exhaust engine design in order to create the 90 engine. The
amount of over-boring
required to extract the extra 15
BHP led to siamesed cylinder bores and piston ring scuffing if the cars were
driven really hard.
The answer was the spread-bore
design in which the cylinder bore centres were re-positioned within the block
to leave more metal between each bore and ultimately to provide better cooling.
September 1956 presented the two
new models for 1957, the "lOSR" and "lOSS". Both used
a high compression version of the 90 engine with twin SU carburetors developing
The lO5R was available in both
standard and deluxe versionS, the standard model being basically a 90 with
Roverdrive automatic transmission. The higher performance engine was required
to offset the loss of power soaked up by the Roverdrive transmission. The
deluxe model was basically an automatic version of the high-spec 1055, but
without the performance or economy.
The lO5R remained in production
for the 1957 and 1958 model years with a total of only 3,540 cars being produced.
There are several theories for
the early demise of the Roverdrive automatic transmission. Some cars did not
perform as well as they could have, while others ran trouble-free for many
years. They became a Rover agent's headache as it was a major operation to
set up and adjust the control linkages correctly. The engine performance was
well down compared with the other models of the P4 range and the fuel consumption
of the 105R was dismal, at a time of petrol rationing after the Suez crisis
The Roverdrive transmission had
been tried during development of the new P5 Rover to give an automatic option,
but it was prone to overheating when coupled to the 3 litre engine. Rover
abandoned further development and settled for the Borg/Warner DC 3-speed unit
for the new 3 litre.
The lO5R had not been a success
for Rover. At Sohhu.U, it had been universally disliked and its acceleration
was considered pathetic. Its sister however, was a totally different story.
The 1055 (the "S" being for sporting) was designed as a high performance
luxury saloon. Its twin carburetor 108 BHP engine gave it a cruising speed
of 90 mph, its occupants travelling in total luxury. The 1055 had virtually
every optional extra fitted as standard, including: twin fog-lamps, front
side lamp reflectors, chrome wheel rim em.bellishers, individual front bucket
seats, cigar lighter, radio, overdrive unit and foot rests for the rear seat
passengers. It also had more powerful servo assisted brakes that were very
efficient even at the higher cruising speeds that these cars were capable
The lO5R deluxe and 1055 by virtue
of their high-spec fittings became the ultimate P4 with no other model being
finished to such a high standard.
Indeed, all later P4's became somewhat
overshadowed by the new P5 3 litre cars.
The end of 1958 saw both the lO5R
and 1055 dropped and the line up for 1959 included the new P5 3 litre as well
as the 60, 75, 90 and 105 models. The 105 was basically a lOSS but without
the high-spec fittings unless specified; which many were. These continued
until September when the entire P4 range was dropped in favour of two new
The two new models for 1960 were
the 4 cylinder 80 and the 6 cylinder
100. The 80 was a 4 cylinder replacement for the 60 and was the only P4 not
to use a variant of the inlet over exhaust engine. The new engine fitted to
the 80 was an overhead valve unit of 2286cc similar to that installed in the
Series 2 Landrover. This had been developed from the Landrover's diesel unit
of 2052cc and developed 77 BHP and was fitted with a solex carburetor and
oil bath air cleaner.
The 100 featured a new 2625cc inlet
over exhaust engine which was essentially a short-stroke version of the new
3 litre engine. This latter engine had been a further development of the spread-bore
90 engine with the cylinder centres again re-positioned~ a seven-bearing crankshaft
and roller cam followers in place of the original pad-type. The 100 developed
104 BHP and was fitted with a single SU carburetor and oil bath air cleaner.
The 80 and 100 were supposed to
be the last of the P4 range of cars. Rover engineers had been working on the
P4's replacement since 1956 and that car - the P6 or Rover 2000 - was originally
scheduled to enter production in 1961.
The P6 project was delayed in 1960
due to delays in obtaining planning approval for a new assembly plant at Solihull.
It soon became clear that this problem would not be settled overnight so work
was temporarily suspended, eventually delaying the programme by two years.
By October 1960, the decision had been made to extend the P4 programme by
two years and this would require another two models being developed at minimum
cost in order to achieve this.
The new models became the 95 and
110 and were introduced at the London Motor Show at Earl's Court in September
1962, alongside the new 3 litre MkII saloon and 3 litre coupe models.
The four cylinder engine was discontinued
altogether with both new models being based on the 100. The 95 was broadly
similar to the 100, using a slightly less powerful 102 BHP version of the
six cylinder 100 engine but with a 3.9:1 rear axle and no overdrive.
The new 110 benefited from mechanical
development work that had been carried out to improve the P5 3 litre. A short
manifold version of the 3 litre's Weslake head was fitted to the 100 engine,
increasing power from 104 to 123 BHP. This gave the 110 the highest top speed
of any P4, although its acceleration was closely matched by that of the 105/1055
After the introduction of the 95
and 110, design and development work on the P6 continued in earnest, with
the car going into full-scale production from September 1963. It was clear
the P4 was nearing the end of its production life, but what if the public
didn't take to the new 2000? Had Rover learned from the public backlash when
the P4 replaced the P3 back in 1949?
The very first 75's had a hydro-mechalliCal braking system but this only lasted
for the first year with an all-hydraulic drum system being offered for the
1951 model year. The braking system was gradually improved with servo assistance
being offered for 1956 but initially only on the 90 equipped with overdrive.
Servo assisted brakes were standard on the 105R and 1055 models. From 1960
onwards, all models had servo assisted girling disc brakes on the front.
The original gear lever fitted
to the 75 was a column change unit, but this was universally disliked and
a floor change conversion was offered by Gethin's, the Rover distributors
in Birmingham. Rover finally gave in to customer pressure and fitted a floor-mounted
gear lever for the 1954 season, coinciding with the introduction of the 60
and 90 models. The long cranked handle was designed to leave legroom for a
third passenger on the front bench seat and was adjustable to suit the driver's
reach. This design remained unaltered to the end of the P4 production and
was also fitted to the first of the P53 litre cars.
The P4 gearbox featured the Rover
freewheel, but a Laycock DeNormanvi]le overdrive unit was optionally available
on the 90 for the 1956 model year and on the 60 and 75 for 1957. Both the
lOSS and 105 models had overdrive as standard. 1959 was the last year that
freewheel was available.
The standard rear wheel axle ratio
was 4.3:1 but in 1955 a rear axle ratio of 3.9:1 was fitted to the non-overdrive
90 which became quite common. The early 80 and 100 models were built without
overdrive, but this was fitted as standard shortly after production began,
so there were only a few 80 and 100 models built without freewheel or overdrive.
The 95 had a rear axle ratio of 3.9:1 with overdrive not being an option on
this model. The 110 had overdrive fitted as standard.
The basic body shape of the P4,
particularly the passenger cabin, did not alter between 1949 and the end of
production in 1964. Body shells were built by Pressed Steel at Cowley with
door, bonnet and boot lid panels of Birmabnght aluminium alloy.
The first P4 75 had the 'Cyclops'
front, consisting of a 15 bar radiator grille with chrome trimming around
the headlamps and air intake grilles. The chrome trimming disappeared and
the 15 bar grille was replaced by an 8 bar grille before the end of the first
year of production. The 8 bar grille, while not as pleasing on the eye, was
more practical and helped to solve the problem of overheating that the early
cars were inflicted with.
The 'Cyclops' front on these early
cars eventuated due to the lighting regulations in effect at the time in Britain.
In essence, they required that the offside or driver's side headlamp should
be extinguished when the lights were dipped, leaving only the nearside or
kerbside headlamp to illuminate the side of the road. For some time, Rover
had added a low mounted "pass lamp" that illuminated the road ahead
without dazzling oncoming drivers, and it is this lamp that gave the early
P4's their nickname of 'Cyclops'. Maurice Wilks had wanted to integrate this
lamp within the lines of the body but it is probable that he had been influenced
by the lines of the 1947 Tucker Torpedo.
The central passlamp was illegal
in the USA and P4's built for the American market had a special cover fitted
over this lamp. This cover had the number 75 cut-out which allowed the light
to shine through which enabled the car to be identified at night.
By the end of 1951, the British
lighting regulations had changed and this allowed the front end of the P4
to be updated. The new chromed grille bore a triangular grille badge similar
to that of the P3 and was a classically simple yet very effective piece of
design. It would remain in use on the P4 models until the end of production
1964, albeit slightly modified over the years. A version of it would also
be used on the new PS model which was introduced in 1958 and eventually went
out of production as a V8 engined P5B model in 1973. So distinctive was the
design that it was re-introduced on cars built by the Rover Group in 1991
and today all Rover models are identified by this grille.
Small changes had also been made
to the rear of the car for the 1952 model season. The small oval rear window
had given way to a wider one and the number plate box was now rectangular,
replacing the original square one. The overall result was that the car now
looked wider and lower from behind and the spare wheel was now accessible
through a flap beneath the bumper.
Two-tone paint schemes first appeared
during 1953, but were limited to two; these being dark grey over light grey
or dark green over light green, the upper colour covering the roof panel only.
For 1954, the home market 90 models
were distinguished by a fog lamp mounted on the left-hand side of the front
bumper, and by a 'Rover 90' in elegant script on the bonnet sides and boot
lid. The enameled grille badges bore the appropriate model designation - "60",
"75" or "90".
In 1953, Rover recruited David Bache who initially became an intepreter of
chief engineer Maurice Wilk's ideas. He had worked at Austin's Longbridge
plant, completing an engineering apprenticeship before moving into styling.
Shortly after joining Rover, he was entrusted with the overall styling of
the forthcoming PS project, with some of his ideas being tested as part of
the upgrading and remodelling of the P4 range.
For the 1955 season, there were
two pressing issues that had to be addressed. The first was that customers
were complaining that the boot of the 1952 - 54 models was too small, and
the second was that the existing rear lights needed to be modified to incorporate
amber flashing direction indicators and red reflectors.
David Rache attended to these concerns
in his 1955 model design which raised the boot line giving a consequential
increase in luggage space. Also incorporated was a much wider wrap-around
rear window and new tail lights consisting of stop/tail lamps, reflectors
and amber flashing direction indicators. The front side lights were given
larger lenses and became direction indicators while new side lamps were fitted
to the top of the front wings, placed in chromed housings.
By the 1957 model year, the PS
design was being flnalised and the front end revision for the P4 would reflect
the new PS stylings. The 1957 models, introduced in September 1956 featured
raised leading edges to the wings with amber indicator lamps incorporated
within them. The side lamps were relocated hall-way down the wing fronts which
were also restyled as part of a general tidying up of the frontal area. The
90 for 1957 had now also lost its distinguishing fog lamp.
The big news for 1957 was the release
of the lO5R and loss models. These were last-minute surprise announcements
on the eve of the Earls Court Motor Show in October 1956 and did not actually
enter production until the end of the year. Both featured a twin carburettor,
high compression version of the 90's 2.6 litre six cylinder engine with a
new cylinder head that featured larger inlet valves for better breathing.
The two SU carburettorS mounted on a water-heated inlet manifold fed the front
three and rear three cylinders respectively, and there was a new exhaust system
with larger-bore pipes than on the 90. The end result was 108 BHP at 4,250
rpm which allowed the 1055 to reach 100 km/li from a standing start in just
over 15 seconds which was a very respectable performance for such a big heavy
saloon in the mid-fifties.
1958 would see the production of
two new models - the Series II Land Rover intended for launch in April, and
the P5 3 litre saloon in September. The Suez crisis had hit sales of P4's
hard during 1957 but now that petrol rationing was over, it was time to revita]ise
interest for 1958. This was achieved by introducing a striking new two-tone
colour split along with a wider variety of two-tone combinations with the
colours being separated.
by a thin chromed strip running
the full length of the car. At first this was only fitted to cars with two-tone
finishes, but early in 1958 it was made standard on all cars, except that
mono-tone cars lacked chrome strips on the leading edge of the front wings.
These changes did appeal to the
buying public with the 1958 season being much better for Rover. Sales of all
models except the 105R were up but it was becoming clear that the 105R was
not proving to be the success that Rover had hoped for. There was nothing
that could be done in the short term to alleviate its failings of high cost
and poor performance3 and so Rover decided to withdraw it at the end of the
1958 season. This was not the end of an automatic P4 however, and there would
be one last attempt to create such a car, although it did not go into production.
1958 had been the ultimate year
for the P4 with the 1055 being Rover's flagship model until September, when
the P5 3 litre was released. From this time on the 3 litre would always take
centre stage with the P4 model range being severally reduced over the remaining
years of production.
The 1959 model year brought the
introduction of the new P5 3 litre and the P4 models received a facelift to
underline the family resemblance. New bumpers and over-riders, together with
a recessed radiator grille and new-style "Rover" nameplate, all
followed the P5 pattern. At the rear a broad chromed embellisher strip was
fitted above the rear number plate which made the cars appear lower and wider
The model range was now also reduced
from five to four models. The 1 05R was dropped in order to protect sales
of the new 3 litre with the automatic option and the 1055 was stripped of
some equipment and reduced in price, again to protect sales of the new 3 litre.
The lOSS now became a 105 and had lost the twin fog lamps, wheel rim embellishers,
cigar lighter and individual front seats that had all been standard on the
lO5S. These options however were available at extra cost.
Most cars of all models for 1959
were supplied with overdrive and this would be the last year for the traditional
Rover freewheel which went out of production at the end of the season.
The 1959 model year was not very
good for Rover with sales of all six -cylinder P4 models being only two-thirds
of the 1958 totals. Sales of the new P5 3 litre were also disappointing, but
this had got off to a slow start resulting from production difficulties. The
four cylinder 60 however did much better with sales actually increasing during
September 1959 brought the next
stage of P4 development which was the inevitable result of rationalisation
of the Rover assembly lines.
A new petrol version of the Land
Rover overhead valve four cylinder diesel engine had been available for the
Series II Land Rover since April 1958 and it was this engine that would power
the new P4 model that would replace the 60 and 75 models. This engine of 2.25
litres developed 77 BHP and went into a new P4 model that was designated as
The new 3 litre PS engine had been
in production since the middle of 1958 and it seemed prudent to develop this
new engine for a new P4 model rather than continue to produce two different
six cylinder engine blocks. A new short-stroke version of the 3 litre engine
was built comprising 2625cc developing 104 BHP that went into a new P4 model
designated the 100. This new car replaced the 90 and 105 models, and buyers
wanting the performance that had been available in the 105 were steered towards
the new 3 litre PS.
Also new for the 1960 model year
was girling disc brakes on the front wheels with the traditional drum brakes
on the rear and the brakes on all cars were now servo assisted.
The option of overdrive had proved
very popular from when it first became available and Rover decided to standardise
this option on both the 80 and 100 models. This decision was made after production
had started and a small number of early 80's and 100's were built without
overdrive, having the 3.9:1 rear axle.
The 80 and 100 models could be
distinguished from their earlier siblings by the dished wheels and recessed-centre
hubcaps that were also fitted to the P5 3 litre. These models still had grille
badges incorporating the model number but only the 100 carried its name in
chromed script on the boot lid and bonnet sides.
As mentioned earlier, the P6 Rover
2000 was originally scheduled to enter production towards the end of 1961
which would allow for a years production of the P4 run -out models with the
final P4 production being the middle of 1962. With the delay of the P6 project,
new P4 models were introduced in September 1962 and there was now no longer
a four cylinder model available.
The new Rover 95 was basically
a de-tuned 100 developing 102 BHP offered without overdrive and a rear axle
ratio of 3.9:1.
The new 110 consisted of the 100
engine but with a version of the 3 litre's Weslake head and developed 123
PHP. This model had overdrive fitted as standard and breathed through a paper
element air cleaner leading to a 2 inch SU HD8 carburettor. This engine had
to rev to 5000 rpm to achieve its maximum power and developed its maximum
torque much further up the rev range at 3000 rpm compared to the earlier engines
at 1500 to 1750 rpm.
With the development of the 110
engine, it is interesting to compare the road performance test carried out
by "The Motor" motoring magazine in July
1957 for the lOSS, with the same test also carried out by "The Motor"
in January 1963 for the 110. A comparison of the results shows that the lOSS
was slightly quicker and also more econonucal than the 110.
Both the 95 and 110 models carried
chromed model identification script names on their bonnet sides and boot lid
but the grille badge was now the standard 3 litre badge so did not carry the
car's model number. The 110 was also distinguished by its full size stainless
steel wheel trims that had been introduced on the 1962 season Mk 1A 3 litre
cars, but the 95 retained the original 100 recessed centre hubcaps with optional
chrome wheel trims.
From March 1963 the Birmabright
alloy panels that had formed the doors, bonnet and boot lid were replaced
by heavier steel panels which added some 75 kg to the weight of the car. One
theory for this is that it was considered more important to divert the supplies
of alloy for the new PG which had it's bonnet and boot lid made from alloy.
The interior of the P4 remained
basically the same over its fifteen-year production run, but minor changes
and improvements were carried out, usually at the request of customers.
The original cars had rectangular
instruments and push button interior door handles. These were changed after
the first season to the conventional lever-type handles. The instrument panel
was also changed for 1951, now sporting conventional circular dials with the
clock repositioned centrally in a new facia rail.
The clock was now visible to the
rear seat passengers as well as to those in the front, the upgrade resulting
in a handsome and restrained facia panel that would be retained in its essentials
for the next decade and a half.
The original hand.brake was a simple
vertical lever located to the right and ahead of the driver, but this was
also modified for 1951 and again for 1953 when it gained its "shepherd's
The 1952 season cars gained a full
circular horn ring in place of the half ring of earlier cars and an organ-type
accelerator pedal now allowed more sensitive throttle control. On the dashboard,
the low-fuel warning light was now replaced by a switch that gave access to
a reserve supply of petrol via a solenoid valve in the fuel line. Rotary switches
also replaced the earlier push-pu.U type and a more powerful heater was installed.
The windscreen was now served by more powerful wipers that had an ingenious
From the start of production the
bench seats had been trimmed in plain leather and this remained unchanged
through the 1955 season. For 1956, pleated seat coverings and optional individual
front seats were introduced. For the 1958 season, the seats were again improved
with the pleated seat coverings being given padded rolls at the edges. These
were covered in plain leather and gave better support for passengers. The
woollen head lining that had been prone to staining, was replaced by a washable
plastic one, available in two colours.
For 1959, interior changes reflected
the new PS model. A padded roll was added to the wood-grain facial rail and
new chromed handles were fitted to the glove box lids. A new style of clock
was also introduced with a chrome bezel containing two adjusting knobs.
The 80 and 100 models were fitted
with a key operated starter switch in place of the push button type and the
later cars were given coat hooks and twin ash trays for the back of the bench
The introduction of the 95 and
110 models resulted in a new instrument panel which shared with the latest
Mk II 3 litre models its clearer instrument faces and the large amber light
that warned that the handbrake was on or that the brake fluid in the reservoir
tank was low. Green direction indicator tell tales were set into the speedometer
and the fuel, temperature and ammeter gauges now had a voltage stabiiser which
prevented their readings from fluctuating. Spade shaped switches replaced
the rotary type and a three-position main lighting switch now incorporated
parking lights. The 110 was fitted with a new windscreen wiper switch that
also operated the electric washers.
A new two-position switch replaced
the petrol reserve solenoid valve and switch. This new switch operated the
main and reserve petrol pumps that consisted of a double-ended fuel pump.
This also had the advantage of providing a "back up" pump if the
main fuel pump should fail while on a trip.
During production of the 95 and
110 models, reclining front seats were available as an option but the front
bench seat was still fitted as standard. Crushable sun visors replaced the
translucent plastic type during the 1963 season and a picnic table/utility
locker was also offered as an optional extra, although this was extremely
rare. Towards the end of production, Rover 2000 style courtesy light switches
replaced the later P4 type during 1964 because their more positive screw fixings
were more reliable than those fitted from 1959.
The Rover 95 and 110 models had
been developed in order to extend the P4's life until the new P6 2000 would
be ready. Rover wanted a years overlap of the P4 and P6 models to cover all
eventualities and to maintain sales until it was clear that SolihnU's radical
new creation would be a true success. It appears that Rover had learned that
the public response does count when a new model is launched. They wanted a
"bet each way" when the P6 was announced and this explains one reason
for the 95 and 110 models being known as Mark I models. Should the new 2000
not be a
success, a revitalised 95 and 110,
to be known as the Mark II version, could be quicldy brought into production
to uphold Rover sales.
Sales of the 95 and 110 held up
well during 1963 but once the new Rover 2000 appeared in October, sales of
the P4 slipped badly. It now appeared that the P6 would be the success that
Rover had hoped for and there would now be no need for the Mark II development
of the 95 and 110.
The 95 and 110 remained in production
through the early part of 1964 and for a little over six months the public
had the choice of P4, PS or P6 models. Once the new 2000 found its market
niche, there was no real point in continuing with P4 production.
The final P4 cars were built in
the last week of May 1964, passing through the despatch department at the
beginning of June.
The P4 was given a fitting send-off
at a special "last of line" ceremony, the final P4 produced being
a home-market 95. Unfortunately the Rover company records and photographic
archives do not establish exactly which car was truly the last P4 or the date
it was built. It is thought that the final build day was the 27th May and
that the last car built had chassis number 760-03293, a burgundy 95. The cars
did not always come down the assembly lines in chassis order; instead each
car was allocated a line number which did run in sequence and this indicates
why it is thought that the last car numerically was not the last car built.
The last car numerically had chassis number 760-03297. This car was a charcoal
95 and appeared in the official company photograph of the "last of the
line" ceremony. These final 95's received no special treatment and were
sold off like all others and sadly no longer exist.
The final 110 built had chassis
number 765-04340 and was a home-market car finished in pine green.
Over the northern summer of 1964, the old P4 assembly lines were ripped out
and replaced by desperately needed assembly lines for Land Rovers. The very
last P4 cars reached their new owners over the next few months, with a few
remaining unsold until the beginning of 1965.