Rover 3500 V8
Ever since it became known that Rover had taken over the manufacturing rights of
the General Motors aluminium V8 engine there have been rumours about what they
would do with it. After much development work to adapt the unit to their own
manufacturing techniques and the needs of their own vehicles, the V8 went into
volume production last autumn as a replacement for the in-line six of the Rover
3-litre. Now it is announced as the engine for a new, supplementary version of
the Rover 2000 to be called the Rover 3500.
Traditionally, in terms of engine size, we in
Britain think small. At first glance therefore, the idea of putting a 3.5-litre
engine into a car originally designed for a 2-litre one seems a bold step. Any
fears about the wisdom of such a move are quickly dispelled by a test drive in
the car, which is as sweet and docile a machine as anyone could wish for. In
fact, several of our testers, keenly awaiting a turn at the wheel, were
surprised to find this was first and foremost a Rover than a sports saloon in
the same class as, say, a Jaguar. In a clever combination of characteristics,
Rover have made sure that the V8 takes none of the sales appeal of the 2000 TC,
which remains a much more eager car for the sporty driver.
Any further doubts are lost forever after a
fast drive on twisty roads. The fine handling qualities of this Rover design
(bracketed together as the P6 range by the factory) show up even better when
there is more response to the throttle, and the 60lb. or so extra weight
compared with the 2000 are barely noticed except as an improvement in the
balance of the car. With a full fuel tank the weight distribution is exactly
50:50, compared with a 53:47 front bias on the 2000.
In terms of power output the V8 develops 168
bhp net at 5.200 rpm, which is 70 bhp more than the 2000 and 46 bhp more than
the 2000 TC. Peak torque comes at 2.600 rpm, slightly lower than on the 2000 but
with a value 86 per cent up. Because a manual gearbox has not yet been
developed, the 3500 is available only with a Borg Warner type 35 automatic
transmission. Some of the sparkle is therefore lost, although automatic suits
the character of the car very well indeed.
To give a high quality of automatic shift,
Rover have deliberately kept the speeds at which the box changes up quite low.
With full throttle and the selector in D1, our car shifted out of bottom at 42
mph and out of intermediate at 64 mph when accelerating. Holding each gear with
the manual over-ride, we went on to 60 mph in bottom and 98 mph in intermediate,
although these speeds correspond to 6.100 rpm, which is well above the peak of
the power curve and the limit of 5.000 rpm which Rover recommend. Engine pull
fades at high revs and the hydraulic tappets "float" well before mechanical
stresses get too high.
Making fully automatic acceleration runs we
reached 60 mph in 11.2 sec. with equal times in opposite directions (despite a 5
mph wind) and 100 mph came up in 43.6 sec. Holding on to the lower gears a
little longer, we cut these times to 10.5 and 37.7 sec. respectively, which
makes a dramatic comparison with the 0 to 60 mph time on the 2000 of 15.1 sec.
The 3500 would be doing 100 mph by the time a 2000 automatic had reached only 82
mph from rest.
On a distance scale the 2000 TC would not be
very far behind the V8 though, the times of a standing-start kilometre being
identical (34.1 sec. and 93 mph), provided the driver of the 3500 does not
over-ride the transmission manually. From 60 to 80 mph, the four-speed gearbox
of the TC gives it the edge with a time of 9.8 sec. in third against the 3500īs
11.5 sec. in top and 12.8 sec. in intermediate.
On out and out top speed, the 3500 is the
fastest Rover yet. In bad conditions of strong winds and heavy rain we recorded
a mean of 114 mph, with a best one way run at 118 mph.
If performance were all that mattered, the
gains from fitting the V8 would not be all that remarkable. The ordinary Rover
2000 engine, though, is only a four cylinder, which means it can never be fully
balanced. A V8 can be made without any residual disturbing forces or couples,
and the 3500īs greatest virtue is the completely smooth and quiet nature of its
power unit. Specifically, the output is very low at only 46 bhp per litre, which
apart from leaving room for developement in future years means that the engine
always has an easy time of it. The lazy, relaxed way it surges forward when
required makes travel far more relaxing.
Being 75 per cent bigger, the engine breathes
that much more at the same revs and the driver can feel the difference as soon
as he puts his foot down. Just as an exercise in flexibility, we timed a run in
intermediate only (by selecting D2) from rest. The quarter-mile came up in 19.8
sec. which is 0.1 sec. better than the time for a manual 2000 using all
the gears up to maximum revs. Throughout the whole of this wide rev range the
engine was quiet and sweet with no more fuss and no vibration at all ever when
spinning at over 6.000 rpm.
Like all Rovers, the 3500 has a manual choke
for its twin SU carburettors with an amber warning light which comes on as soon
as the engine has warmed enough for the control to be pushed back. Starting is
immediate, hot or cold, and there is no hesitation during the warming up period.
With all the low speed torque available, the extra losses when the gearbox oil
is cold do not stand out like they do with a smaller engine.
As mentioned earlier, the automatic change-up
speeds have been set low, and this means that the maximum kickdown speeds are
low as well. It is impossible to kickdown into intermediate above 52 mph and the
speed must have dropped to 30 mph before bottom can be brought in without
resorting to the stick. There is also an annoying delay before kickdown
selection takes place, and we would much prefer a D-2-1 selector system with
provision for part-throttle downshifts.
One of the changes made to cope with the extra
power has been to fit larger section tyres - 185 instead of 165-14 in. These
raise the gearing even more than the accompanying axle change from 3.54 to 3.08
to 1, and also make the steering heavier, particularly when manoeuvring at slow
speed. Somehow with automatic and a big engine one expects power steering, but
this is not available. There has been no sacrifice of lock to get wheel-arch
clearance for the fat tyres and the turning circles of just over 33 ft. between
kerbs are every bit as compact as on a 2000. There are now 4.5 turns from lock
to lock, instead of 3.9, which is not a big enough difference to be noticed.
Basically the Rover 3500 is an understeering
car and despite all the extra power it is still not possible to get the rear
wheels to slide unless one corners really fast, and by then there is an
uncomfortable degree of body roll. Initially the car goes into a turn stably,
with the steering effort increasing in proportion to the radius of the bend and
the speed at which it is being taken. Just at the point where strong understeer
might begin to be an embarrassment, roll affects the rear end and brings the
tail out just enough to line the car up correctly again. What most owners will
experience, though, is positive response to wheel movements without the sudden
alarm of the front running wide or the tail flicking out in slippery conditions.
There is a lot of roll when the Rover is
cornered fast, and it feels at first as if the initial swing on the wheel is
merely twisting the front of the car into the turn. This roll is never much of a
disturbance because the seats all wrap round well enough to hold the occupants
in place. It does not seem to worry the car if there is road camber or bumps in
the gutter; it keeps to a straight path regardless. Stability in strong cross
winds is really quite good, although it takes a while to get used to the way the
wheel "works" back and forth through oneīs hands when driving in the 100 mph
plus bracket. The rear suspension sets up a kind of rocking motion (like an
express train), but this is only slight.
Long and relatively soft wheel movements make
light work of uneven surfaces, and the Rover is particularly impressive on
long-pitched undulations like those at the edges of most French roads. When the
road is really rough the rear suspension can be heard working hard and the
bigger tyres seem to thump more loudly on sharp ridges, but generally the level
of road noise is very low.
Front discs for the 3500 are 0.5 in. bigger in
diameter than those of the 2000, but otherwise the breaking system -
originally Dunlop but now Girling discs with Lockheed servo - is much the same.
Pedal loads are even less than before, barely 60 lb. being needed now to obtain
a 1g stop. It was interesting to find that with the new low-profile Avon radials
tyres fitted, it did not matter much to the ultimate braking figure whether the
wheels were locked or just on the point of being so. Fade resistance was
excellent and the brakes seemed to work even better from 70 mph than from 30
mph. The reassurance of a really powerful high speed stop, with that progressive
feel of a giant hand pulling the car back, was most impressive; this must be one
of the best braking systems on any car today.
The handbrake managed to stop the car with 0.4g
from 30 mph, and it held easily facing either way on the 1-in-3 test hill.
Restarting, of course, was no problem.
The rest of the 3500 is just like the 2000,
except for the badges and one or two other details, like the deeper chin under
the front bumper. The shelf across the top of the facia has a "prickly" rubber
mat to stop objects sliding about (this is available as an extra for the 2000)
and there is a rectangular panel in front of the driver containing the
speedometer and supplementary gauges and tell-tales.
Driving position is very much of "upright
chair" type where one sits with the calves almost vertical above the pedals.
Both the pedals - wide, left or right foot brake and accelerator - are on the
same level so that there is no dangerous lift from one to the other. The
steering wheel can be adjusted for rake, with a unique friction clamp that will
lock them at any angle.
At first the switches and knobs seem to be
scattered about the facia almost at random, but with familiarity the driver
finds the systematic placing of them and the way they work (in particular the
lightning controls are unusual) very sensible indeed.
As well as a versatile and sensitive heating
system, which blends hot and cold air to give the chosen temperature, there is a
cold air system which ducts boosted air to two slots on the facia rail from
where it can be directed directly to the face without freezing oneīs hands.
There is reserve of fuel, operated by a knob on
the central console matching the choke. When we tried it, the cable jammed so
that we could not switch back to normal.
One disappointing thing about the 3500 is the
fuel consumption but this is mainly in contrast with the 2000 which is
economical for its performance. Overall we recorded 17.3 mpg during a test
distance of almost 1.400 miles. The fuel tank takes an extra 3gal (15 instead of
12), but the range was still only 240 miles before we needed to switch over to
the 1 1/4-gal reserve.
Overall the 3500 is a very pleasant car to
drive, and as we originally said of the 2000 back in 1963, it is bound to find a
whole new sector of owners among the motoring public. If the 2000 can be
criticized at all, it is on the grounds of its none-too-smooth four cylinder
engine and that complaint is more than answered with the 3500. Cleverly priced
about halfway between the 2000 TC and the big 3.5-litre saloon, the 3500 will
become a satisfying and compact gentlemanīs carriage for the upper set and
provide a much refined step-up for those graduating from the "lower set".
Autocar / UK
April 1968
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