Britain's Autocar magazine (weekly)

Auto Test: MGB GT V8

MG Elegance, Rover Smoothness

as published in British V8 Newsletter, Volume XV Issue 3, December 2007

Re-printed unedited by exclusive written permission of "Autocar".
This article originally appeared in their issue for the week ending August 16, 1973.

Effective combination of proven MGB GT and superb Rover 3500 V8. Good performance with remarkable economy. Smooth fuss-free engine with good torque but little engine noise. Perennial MGB faults. Too expensive.

Few cars have been more of an open secret than the MGB GT V8. From the moment that supplies of the Rover V8 engine to Ken Costello were stopped, it was clear that British Leyland themselves were intending to do a similar exercise.

There is a considerable market all over Europe and America for a smart Grand Touring car with comfortable space for two people and their luggage, or for two and their small children or their dogs, and such cars as the Reliant Scimitar GTE and the Lotus Elan +2 have sold well as a result. It must also have worried British Leyland that they were not represented in the "big" sports car range by the Austin Morris Division, following the termination of the Austin Healey 3000, and the unfortunate public response to the MGC that led to its early demise. As we said when the MGC was first tested, if there were no MGB by which to measure it, the MGC would not have been considered such a bad car, and so it is heartening to see that British Leyland are again prepared to capitalize on the excellent name of "MG" and to try again.

Pininfarina Italian styling
The elegant Pininfarina-inspired lines are unaffected by the change in power unit, revised manifolding avoiding the
need for a re-shaping of the bonnet. The familiar MG insignia on the radiator has returned to its previous position at
the top centre of the grille surround, while the surround itself has returned to the shape and size that it was before
the 1971 revisions.

The combination of the timeless lines of the Pininfarina-influenced MGB GT and the smoothness of the lightweight 3,528cc Rover V8 engine ought, on paper anyway, to make for an excellent high performance sporting coupe. If the end product falls short in any way, it is in the unfortunate perpetuation of the dated features of the MGB. Such shortcomings as excessive wind noise, a harsh ride, and heavy steering may be forgiven in an out-and-out sports car, but they have no place in a GT car costing over £2000. More unfortunate still is the fact that such shortcomings are accentuated by the superb smoothness and relative quietness of the excellent Rover V8 engine, which it must be admitted goes most of the way to making up for the less likeable facets of the car.

In terms of performance, the Rover engine has moved the MGB GT V8 up into the realms of the fastest European sports cars as it is capable of well over 120mph and its acceleration both through and in the gears is excellent. Acceleration from rest to 90mph in under 20 seconds, and a standing quarter mile time of 16.4 seconds are both very good, and the effortless way in which the quiet V8 accelerates from as low as 10mph in top gear is impressive. In direct top-gear, each 20mph increment from 10 to 80mph takes less than 8 seconds, while it takes only 10.3 seconds to get from 80 to 100mph.

To provide this sort of performance, while paying attention to European Emission Regulations, British Leyland use a version of the V8 engine that has most in common with the Range Rover, utilizing the same low-compression pistons in both engines. To allow for a sufficiently low carburetor height, the manifold is changed from the penthouse design of the Rover 3500 and Range Rover, and a cast manifold is used, whose inlet tracts point towards the back of the engine enabling the carburetors to be positioned close to the bulkhead, where there is more available space.

Rover V8 engine
There is little to show that the Rover V8 engine is not the original power unit of the MGB GT V8, as the installation is
neat and well planned. The electrical service items such as fuses and relays are all positioned on the offside of the
bay, while the radiator header tank and screen washer reservoir are on the nearside. The reservoirs for clutch and
brake hydraulic circuits are positioned high up behind the pedal box, but their proximity to the angle of bulkhead
and bonnet makes it difficult to see the fluid level. (Photo by Ken Smith. Used by permission.)

 Please support the sponsoring companies who make BritishV8 possible, including:

The gearbox derives from the MGC all-synchromesh unit that was introduced on all MGBs in 1967. As used on the MGB GT V8, only the casing is changed to allow the use of a 9.5 inch diameter clutch, while the internal ratios are higher than those of the 4 cylinder car to suit the increased power and torque of the much larger engine. The ratios are well chosen, allowing up to 40mph in 1st gear, and 100mph in third gear. Although 2nd gear gives up to 60mph, it is spaced a little too close to 1st gear and would benefit from being a little higher.

Overdrive operates on top gear only and is geared up to give 28.5mph/1000rpm. While this may seem to indicate a strictly "overdrive" gearing, it is surprising how often it can be engaged, even around town, so torquey is the V8 engine. Engagement of the overdrive is by the lefthand of two fingertip stalks, and while the unit disengages sweetly enough when the lever is pushed away from the wheel rim, engagement is lazy and unduly speed-conscious, taking longer to engage at low speeds than high, as the inhibitors sort themselves out, and decide whether or not overdrive can be engaged.

Enjoying this article? Our magazine is funded through the generous support of readers like you!
To contribute to our operating budget,  please click here and follow the instructions.
(Suggested contribution is twenty bucks per year. Feel free to give more!)

One of the nicest features of the car is the complete absence of any snatch, vibration, or harshness from the drive-line. From full throttle to overrun, there is little sign of the considerable torque reversals that are taking place, and this contributes greatly to the pleasure of driving the car. As this feature is present to a lesser degree in the Rover 3500S it is probably due in part to the V8 engine, but the very short propshaft must help considerably in this.

There are absolutely no dramas involved in starting the car, either cold or hot. Under cold-start conditions, the manual mixture enrichment needs to be used sparingly, and can be pushed home within the first mile. In fact, the car runs smoothly without the need for enrichment long before the heater starts to give much appreciated warmth.

Despite a good angle of attack, the clutch effort is inordinately high, and operating it becomes a tiring exercise in town. Perhaps this is more noticeable as the full movement must be used to avoid any grating on engaging the gears. It is essential to use the full movement of the clutch when engaging reverse, as the gears continue to spin for a long time, and it is often quicker to stop them by engaging first gear. The gearchange is also appreciably heavier if the full travel of the clutch is not utilized.

The brakes are excellent, progressive and capable of producing a 1g stop at only 65lb pedal load; the accelerated fade tests revealed only a slight tendency for the pedal load to increase as the brakes became hot, and only on the 10th application from 70mph did they begin to show any loss of performance, and that only slight.

All the MGBs are commendably tractable, and very easy cars to drive. They can all be pottered gently without the need for critical use of gearchange points, and the V8 version distinguishes itself by being even more free of fuss than its smaller-engined brothers. Never before has a sports car in this class been as flexible and forgiving and so easy to drive smoothly, but then again never before has such a smooth engine been offered beneath an MG bonnet.

What is remarkable is that this marked increase in performance and flexibility is accomplished at little cost in fuel economy. Compared with the last MGB GT that we tested two years ago, the V8 gave 23.4 mpg overall, compared with 23.7mpg overall for the smaller-engined car. While it would be possible to get a slightly better "touring" performance from the four cylinder car, this is partially offset by the fact that the Rover V8 engine can run on three star fuel, while the four cylinder engine requires five star, and we would expect that the same driver on the same journeys would get very similar figures in the two cars. When the considerable difference in performance is taken into account, this is a quite outstanding achievement.

Ride and Handling

To cope with the 75 per cent increase in torque that the V8 has brought, the spring rates have been increased at the rear. There is a small balancing increase at the front that goes unnoticed, but the harder rear springs have turned the ride from hard to harsh, compared to the earlier MGB. This excessive rear end roll stiffness contributes to power oversteer that is in conflict with the natural understeering characteristics of the car. This is not a problem on long sweeping fast bends, but at lower speeds hard acceleration can produce a disconcerting imbalance as the transition from understeer to oversteer takes place. Further evidence of the imbalanced nature of car appears when one is forced to lift-off in the middle of a corner that has been entered at too high a speed to allow power oversteer to be induced. If the lift-off is sudden, the car tightens its line quite abruptly, necessitating rapid steering correction. Considering how very predictable the normal MGB is, and how predictable the Costello MGB V8 is, it would seem that the work on the rear suspension has not produced the desired results. It must not be assumed that the foregoing ascribes a serious degree of raggedness to the handling but since the MGB GT V8 must put down half as much power again as the four cylinder car and at the higher potential cornering speeds that the excellent Goodyear G800 tyres allow, it would inspire more confidence if the handling was more progressive. Extremely strong castor action contributes considerably to excellent straight line stability. It also makes for good resistance to side winds, but means fairly heavy steering effort.

Interior comfort and fittings

Many young families would consider the MGB GT V8 an ideal car for parents and children up to seven or eight. With the children on the back seat, there is still sufficient room behind for a great deal of luggage, and if the children are to be left at home, the rear seat can be folded forward, further increasing the available load space, and leaving room for such bulky items as school trunks or pram bases. Access to the luggage space is gained through the large rear door that swings well out of the way, and is retained in the open position by two sturdy self supporting struts. The spare wheel is housed below the floor of the load space, and is properly secured by a large wing nut. The area around the spare wheel can be used to stow tools and oddments that would otherwise be on display in the luggage area.

In the remainder of the car, stowage space is limited to a small glove locker (which, as we have said many times, is infuriating as it can only be opened and closed by the key, which is inevitably on the key ring, where it belongs.) and to a lift-up glove locker between the seats whose aptly described by its title. There is also a useful map pocket on the passenger's side, but this is out of reach, especially when static seat belts are being worn.

MGB GT rear seat
The rear seats are really only suitable for children up to about eight, although no doubt older children would put up with
discomfort for the thrill of being driven in the car. The rear seat cushions are retained by "lift the dot" fasteners, and when
released allow the rear seat back to swing down onto the rear seat.  -  A surprising amount of luggage can be fitted into
the load area, and the two wells behind the rear wheel arches are particularly useful for stowage. A pram base will not
quite fit crossways between the wheel arches, and will not fit longways if the rear seat is in the raised position.

All the seats now have nylon facings on their wearing surfaces, and both the front seats can be reclined. Adjustment of the front seats is generous and drivers of all sizes can be accommodated. The backs of the front seats do, however, lack lumbar support and leave a space below the small of the back that can lead to some discomfort. The seat backs are high and well-shaped, providing good shoulder support, and the gripping nature of the brushed nylon material helps to provide good lateral support. The backs of the seat recline, but only to approximately 45 degrees at which angle they come up against the rear seats.

For the driver, the seating position relative to the controls is good, the gear lever falling comfortably to hand, and the relationship of shoulder position to the small leather-covered steering wheel enables a near straight arm posture to be enjoyed. Shorter drivers do, however, tend to sit quite low in the car, making visibility of the front corners difficult.

roomy interior of the MGB GT
The roomy interior of the MGB GT remains substantially unaltered, only the size of the instruments and calibration of
the speedometer to 140mph indicate the presence of the V8 engine beneath the bonnet. Unfortunately, the opportunity
has not been taken to level up the pedals and therefore it is still not possible to heel-and-toe.

The remainder of the interior appointments are in line with the normal MGB GT, with the exception of the speedometer and rev counter, which are the same small size as the American market cars. This is dictated by the larger shroud made necessary by the additional finger tip switch for the overdrive.

Living with the MGB GT V8

Static seat belts at £15.85 including VAT were the only optional extra on our MGB GT V8, and so the price of £2293.96 had only the normal items of vehicle license/delivery charge (including VAT) of £18.70 and number plates of £5.00 to give an on-the-road price of £2352.43. The MGB GT V8 package includes all the items that are available as options on the normal MGB GT. Included among these heated rear window, tinted windows, servo brakes, head restraints, and of course the overdrive unit.

There should be few problems involved in getting nationwide service for the car, as Laycare now extends to all British Leyland dealers, and this ensures fixed charges for routine servicing anywhere in the country, and also ensures that there are technicians capable of servicing the Rover V8 engine at all MG dealers. The cost of replacement parts is expected to be similar to those for existing MG parts, while prices for the Rover engine should not be excessive.

Routine servicing is recommended every 6,000 miles, while a "safety check" service is recommended every 3,000 miles if the car is used under dusty or arduous conditions. Access to items requiring routine maintenance is good beneath the big aluminium bonnet, and a typically thoughtful feature is a plastic grip on the dipstick, which remains cool. The engine has a no-loss cooling system, and it is essential to check this while the engine is cool.

The electrical circuits are protected by four fuses in a fusebox, while there are two additional inline fuses to protect the heater fan motor and the hazard warning flasher unit.

The spare wheel lives below the floor of the rear luggage compartment from which all luggage must be removed in the event of a puncture. However, as the spare is inside the car, it stays clean and dry, although it must be released from its stowed position and turned over for its pressure to be checked.

The rear compartment of the test car became saturated with water during the course of the test period. At first, poor sealing around the tailgate was suspected, but as the water only gets in when the car is on the move, we would suspect that the grommet around the petrol filler cap was not a good fit. This problem has been noticed with previous MGBs, and attention to this seal at the early stages is advised.

There are no tools supplied with the car apart from a jack and wheelbrace which are stowed in a substantial soft bag in the space occupied by the spare wheel. There is one jacking point on each side of the car, and the jack has a good crank action, raising the car quickly.


To put the MGB GT V8 into perspective in the new market that British Leyland are entering, it must be compared with a number of cars that have already carved a niche for themselves. For instance, there is the Reliant Scimitar GTE at £2,439 or £2480 with overdrive, the Datsun 240Z at £2535, the Lotus Elan +2 S130 at £2789 and of course the Triumph Stag at £2533, while the Ford Capri 3000 GXL compares favorably at only £1824.

To hope to sell well against this powerful competition, the MGB GT V8 has to rely heavily on its excellent smooth power unit, for in most respects of appointment and comfort it does not score over the opposition. In terms of handling the MGB GT V8 scores over all but the Datsun and the Lotus Elan +2, while in terms of ride, it must be rated at the back of the field. In view of the fact that the development costs cannot have been high, it is difficult to understand how a £500 differential can be justified between the MGB GT V8 and an MGB GT with the four cylinder engine, and the same optional equipment. Undoubtedly the car will sell well on the MG name alone, but it is a fiercely competitive area that the MGB GT V8 has stepped into, and if it succeeds, it will be mainly due to the excellent Rover V8 engine for which praise cannot be too high.

BritishV8 Magazine has assembled the largest, most authoritative collection of MG "MGB GT V8" information you'll find anywhere. Check it out!   Access our MGB GT V8 article index by clicking here.

British V8 Home:        Read the Magazine        Photo Gallery        Web Forum        Annual Meets        Contact Us        Site Map