Classics for 1974: MGB GT V8
as published in BritishV8 Magazine, Volume XVII Issue 1, July 2009
Re-printed unedited by exclusive written permission of "Classic Car".
This article originally appeared in their inaugural October 1973 issue.
It would be unkind to extol the virtues of the new MG under a 'return of
the big Healey' banner, but this is certainly the nearest in the British
Leyland sports car range to the last of the Austin Healey 3000s. Anyway
the big Healey has returned in between, first as the lamentable but lamented
MGC - killed by the press but improved too late to recover - and the
Datsun 240Z. The MG V8 is a muscle car in performance terms with all the
charming practicability of the MGB GT in an uprated shell.
Despite strong denials of its existence, even in the face of the well-known
Costello productions, British Leyland started work on this car in summer 1971.
Market research had shown that large production sports cars stay around for
some time - inevitable with fewer cars to carry tooling costs - that there
was a market gap for a developed sports car to compete against the sporty
coupes, and that there was a trend for sports cars to have engines over
2.5-litres. The compact, lightweight Rover V8 developed from the Buick engine,
was an obvious choice. In basic terms it is 40 lb. lighter than the cast-iron
MGB 1.8-litre but by the time the anti-noise, anti-emission ancillaries have
been added the power plant is heavier than the original.
Inevitably the recent safety and emission laws have taken a lot of
engineer's development time for no outward difference; this has put
off more than one model launch and has certainly delayed the arrival
of this one. So it wasn't just a question of slotting a clean V8 into
an existing design. In keeping with the low-octane fuel requirements
the compression ratio has now been lowered to 8.25:1 for 94-octane fuel;
to maintain the normal B bonnet line twin SU's are mounted at the back
of the engine, facing rearwards and breathing through a pair of pancake
filters on top of the camboxes; these inhale the general underbonnet
air and from a collector over the exhaust manifold, with a bimetallic
valve adjusting the quantities of hot and less-hot air. Against the
quoted 180 gross bhp from the original 3500 engine, the B version now
produces 137 net bhp, or under 50 per cent more than the original
1.8-litre. The new torque figure - 193 lb.ft. - is the best reflection
of the capabilities of the larger engine.
To fit it in, changes have been made to the bulkhead and to the front
cross member while the wheelarches have been reshaped to clear the
exhaust plumbing. The gearbox is a re-ratioed MGC one with higher
intermediates (much nicer) and a larger bellhousing for a bigger clutch.
Giving maxima in the gears of 41, 64, 99 and 124 the ratios are very well
chosen to give that equal mph span per gear (apart from first) that gives
ideal acceleration. A Laycock overdrive on the back gives an 18 per cent
rev, drop which is ideal for fast and effortless cruising best reflected
by fuel consumption improvements of 10 per cent or more over 80 mph. The
final drive at 3.07:1 is also from the MGC. To cope with the extra torque
the leaf rear springs have been uprated and so have the front coils,
partly to maintain the balance of roll and pitch rates and also to
compensate for the extra weight on the front wheels. The steering rack
has been moved to lighten the steering by decreasing castor as the tyres
are a section up on standard GT at 175HR-14. These are mounted on 5J wheels
with cast alloy centres riveted to chrome steel rims.
Virtually unchanged from that of the MGB GT, the interior for the V8 is spartan
for the price with its rubber matting and crackle black metal fascia.
Somewhat disappointingly, the facia layout is virtually unchanged; the
fresh air grilles of recent adoption are good but the rotary heater
controls have never been easy to use. Rubber flooring doesn't really
live up to the new big GT image but the seats are an improvement with
good adjustment.
Not only does the big V8 sound quite different, it is also a lot quieter
from the moment it starts than the old B-series unit. Even when wound up
to 5000 rpm it is still only a muted thrum which you only begin to notice
around 3000 rpm - 85 mph in overdrive top. Obviously the MG engineers have
done a good job on mountings and insulation. Cruising along at 70 mph is
very restful, apart from a certain amount of curable wind-noise and is
quite easy on the pocket too at 275 mpg on 3-star fuel. A torque-engine
capable of pulling strongly from around 1000 rpm means that most of your
motoring will be in third and top, in 600 miles of out-of-town running we
recorded 23.2 mpg which compares very well with a staff Jensen-Healey
which makes harder work of similar averages for 20 mpg.
Actual figures of 0-60 mph in 7.7 seconds and 30-70 mph in 12 seconds in
3rd tell most of the story. We didn't check the maximum speed but the
factory claim 124 mph at 5300 rpm in direct top, just 300 rpm over the
peak. Overdrive, engaged by the washer/wiper stalk on the column, doesn't
help outright performance. If you want to play tunes on the gearbox it
is very nice to use but not really necessary, except perhaps in the Alps.
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The chassis is the least satisfactory part of the marriage; when the MGB
first came out in 1962 with the usual wishbone front, leaf spring live
axle rear layout, the ride was reckoned to be very good. Alright, it
rolled more than the MGA, but the ride was definitely good for a sports
car of that era.
With the BGT in 1965 it was firmer but still quite good, the roadholding
on the 5J wheels which were standard was certainly good enough for all
normal road use. Now with the GT V8 and stiffer springing all round the
ride is poor particularly by modern standards; others have shown that a
live axle ride can still be good. On most main roads it is quite
acceptable and there is very little road noise, but on bumpy roads it
feels as though most of the road amplitude is passed to the occupants.
Uncomfortable at times.
Somehow the car feels heavier than the 1.8 B GT, but more solid due to
better insulation; the steering is direct but firm and kickback is minimal.
Roadholding on big tyres is good within the limitation imposed by the
surface and you can throw the car around quite happily; it takes a lot of
power to shift the tail on wet roads too.
Seats and driving position are good and most sizes can find a comfortable
position with good visibility. With the back seat, strictly for [children]
under 7, folded down there is a useful luggage area and it is easy to load
through the lift-up tailgate.
The great charm of the MG's is that they are thoroughly honest vehicles
which will never get you into trouble; they are always predictable and
essentially reliable. At its best on open roads as a long legged tourer
it is just as suited to shopping trips. There is just one drawback - the
price at £2310 including the nice inertia reel seat belts is rather higher
than expected. You could have the Rover 3500S for the same!
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