Behold the MGB V8

as published in BritishV8 Magazine,
Volume XVI Issue 2, October 2008


Re-printed unedited by exclusive permission of "Australian Motor Manual".

This article originally appeared in their issue for October 1973.

by: Armstrong


A NEW MG is always news, because it doesn't happen very often and, although the MGB GT V8 (whew, what a mouthful!) is a hybrid, it is the fastest, smoothest, largest-engined production MG yet.

The near-50-year-old company in the sleepy Berkshire market town of Abingdon-on-Thames have, in effect, put a light-alloy Rover V8 Motor in the familiar GT coupe unitary body, and transformed the performance of the basic model, introduced in 1965.

With overdrive as standard equipment, the 3528cc eight-cylinder fastback will nudge 125 mph, and cover a 0-60 mph in 84 seconds yet, with all this performance, it displays almost uncanny flexibility.
  Behold the MGB V8

In direct top it will throttle down to 10 mph and potter along without a complaint, then (on 97 octane, four-star fuel) it will accelerate strongly, without any sort of snatch, when the accelerator is floored.

I found I could extract a 10-50 mph in top in 13 seconds, which can't be bad, and all-round fuel consumption is about 23 mpg.

By the same token, a 40-70 mph - the sort of acceleration sector that is called for so often in this day and age - can be had in nine seconds, in top. Even in overdrive (28.5 mph per 1000 rpm) the MG V8 will chuff along at 18 mph, not minding a bit, and all such maneuvers are carried out in Rover-type silence.


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In spite of the limousine manners the V8 is a real goer - first gear will slide it up to 40 mph, second to 62, third to 98, fourth to 122 mph, and fifth, with a good run will take the needle round to 125 -- at around 4500 rpm. The overdrive is more a fuel, wear, and noise saver then a performance-plus accessory, but if the run is long the speed will mount up. Even with direct top, 100 mph represents not much more than 4000 rpm (32.4 mph per 1000 rpm), so the going is always leisurely.

Through the gears, 100 mph can be reached in 26.5 seconds, and the standing quarter-mile is on-in 16.5 seconds.

As you will see from the accompanying pictures, the 'V8' looks little different from the 1.8-litre 'B', except for rather handsome Dunlop light-alloy road wheels (with cast alloy centres riveted to chromium-plated steel rims), a few V8 badges, and a slightly higher look.

The latter is due to the fact the new model is one inch higher than the 'B' - a situation which has come about because of the line production system of fitting the Rover engine.

MGB GT V8 promotional photo (YWL 921L)


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Having the car set-up an inch higher makes it easier for the operatives to install the motor, and to streamline production of both models, the 1.8-litre car will also be raised an inch in the near future.

The interior is almost identical, except for the 140 mph speedometer (instead of 120), and for the excellent nylon 'corduroy' seat materials.

Like the smaller-engined MGB, the V8 has the lift-up window/tailgate and the laughable rear seat which folds to accept a great deal of luggage or whatever. With the seat folded-down, to be fair, their is space for a couple of kids, providing their legs aren't too long. Should be a good car to export to Japan!

No one is more critical of driving positions than I am but, I'm bound to say, I found the V8 very palatable. Except, for the fact that I was forced to slide the driver's seat forward one click more than I wanted, due to the clutch which needed to be pushed to the floor for disengagement.

The clutch is obviously strongly-springed to cope with the 193 lb. ft. of DIN/torque (at 2900 rpm), and what with the long movement, and the need for the pedal to be floored, one has to sit forward more than one would like.

That observation applies to a five foot eleven driver who likes to get back from the wheel - especially in spirited cars which respond to spirited driving.

The clutch, I would imagine, will make the new MG a bit of a problem for lady drivers, and from what I was told at Longbridge, it seems unlikely there will be an automatic at a later date.

The gearbox is from the six-cylinder MGC (no longer produced), but has modified internals. It has synchromesh on all four speeds, and the overdrive is engaged by a clever stalk on the left of the steering column which engages with toward-the-driver movement, and disengages when pushed away.

The stalk also controls the two-speed windscreen wipers with up and down movements. As if that isn't enough the overworked stalk also operates the electric screenwasher when pushed inward.

It's all right when you make the overdrive maneuver in text book fashion, but I'm bound to say I squirted the windscreen more than once when engaging overdrive.

I also found the overdrive disengaged immediately, but was leisurely when engaging. No doubt the latter arrangement saves wear and tear on the transmission, but I like my gears to go in when I want them to - and quickly. The gearbox itself was fair enough, but it wasn't enhanced by the already-mentioned clutch.

stylized V8 badge on the MGB grille
Discreet badge warns other MGB drivers to keep clear.
V8 will in fact propel the car to 125mph.

British V8 editor's note: this stylized view of the V8 badge on the MGB grille has appeared
many places over the years. The first use we've found for this image was here in the October 1973
edition of Australian Motor Manual magazine. We've enlarged and refined it for our online use...

Having said that, it must be recorded that the MGB GT V8 is an utterly satisfying car to drive. Handling, with the weight-distribution (two-up) of 49.4/50.6 percent, is virtually neutral. If anything, the new MG very slightly understeers with the throttle on, and very slightly oversteers with it off.

Steering, however, is heavy and, in fact, requires strong wrists when corners are being taken fast with plenty of throttle on. The rack and pinion steering gear is high-geared at 2.93 turns from lock to lock, but again, I would think a lady driver would find it a struggle.

The ride is hard, yes hard, particularly at low speeds. The usual MG dictum has been pursued, the live rear axle being un-located by anything else other than the semi-elliptic springs. To keep the axle under control, and to offer precise handling, the MG engineers have mounted the casing on three massive spring leaves.

It locates the axle remarkably well, but those short, stiff springs make for a hurdle-like ride, particularly at low speeds.

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I talked to Roy Brocklehurst, chief engineer of the MG V8 project, and he told me his brief was to produce the new car with as many existing bits as possible. I told him I thought the V8 would have been even better if the springing had been softened, and a Panhard rod or A-bracket had been utilized to positively locate the rear axle. He smiled and repeated his brief.

Roy also told me, when I commented on the heavy steering, that the rack had been mounted further forward with the V8 engine, and that a little of the Ackermann action had been lost. "It's so little it isn't worth worrying about", he said, and added that the 1.8-litre car would also be getting the forward-mounted rack and pinion assembly to streamline production in the very near future.

The new car brings home what we are having to suffer to placate the emission gods. The new V8 started off with its light-alloy engine some 40 lb. lighter than the old 1.8-litre cast-iron four-cylinder unit, but with the necessary equipment added to combat emission, noise, and to add safety, the weight is just a little more than the old engine - which continues in production, by the way.

early pre-production or prototype MGB GT V8
British V8 editor's note: this photo shows an early pre-production or prototype MGB GT V8!
Specifically, it shows a radiator-mounted sheetmetal fan shield for an engine driven fan.
Engine driven fans (and these shrouds) were never used in production MGB GT V8's.

To keep the bonnet line civilized and to avoid that dreadful 'power bulge' which was a feature of the ill-fated six-cylinder C-type, the twin SU HIF 6 carburettors (with 'horizontal integral float' chambers) are installed at the rear of the motor on specially-designed low-line inlet manifolds. I never experienced any sort of flat-spot while driving the V8, so the integral float-chambered SUs obviously provide stable carburation.

Another space-saver is the AC-Delco alternator. From General Motors!!

When you get down to it of course, the engine originally came from GM. It was first conceived as a light-alloy V8 for the Buick and Oldsmobile 'Compact' series some eight or nine (sic) years ago, but GM wanted it to be a very high-volume die-cast pressure/engine, as well as a lightweight one, and their scheme was to produce it as an 'all light-alloy' motor, with the pistons running direct in the aluminium bores (sic). The idea was to cut machining time to a minimum, and to really churn out the blocks.

Well, it didn't quite work out like that, and relatively few were produced. (British V8 editors note: GM produced more aluminum V8's in three years than MG produced MGB's in 18 years... but no matter.) The cars were ultimately manufactured with different engines, and, when Rover's M-D Martin Hurst heard of the motor sitting on the floor, he rushed over to Detroit to talk to GM brass with a view to buying the design and manufacturing rights.

GM said yes because Rover's requirements were different. They didn't plan - nor did they have the capacity - to produce vast quantities for their '2000', and Hurst's idea was to sand-cast the block and fit cylinder liners. (British V8 editor's note: the GM-produced aluminum V8's also had iron cylinder liners...) Which Rover's did, and very successfully.

Almost at the same time, Repeo negotiated the block design for a racing engine. As a three-litre with a single overhead camshaft per bank it is now history that Jack Brabham swept all before him in the new 1966 Formula 1, and earned himself (another) World Championship.



Now, in one form or another we have the light-alloy V8 in Rover 3500, Range-Rover, Leyland P76, Morgan Plus Eight, and MGB GT V8.

With its American-Anglo-Australian background the V8 is certainly an international power-unit. It is a fact the five-bearing, short- stroke motor endows the new MG with almost twice the power and torque of the 1.8-litre model.

The compression ratio has been dropped to 8.25:1 from the 10.5:1 of the Rover 3500. This modification of course is carried out to reduce exhaust emissions, and to give the engine a 97 octane fuel requirement. In spite of the lower compression, power-output (DIN) is 137 bhp at 5000 rpm, compared to the Rover's 151 (DIN) bhp at 5200rpm.

As set-up, the MG V8 engine meets all European emission rulings, and with an exhaust air pump will pass U.S. Federal requirements as they are at the moment. For the future, the exhaust may have to be equipped with a catalyst to pass American rulings, but Roy Brocklehurst told me that the entire market was under review.

"We have the equipment on ice", he said, "but in the long-term you have to assess the value of the market. Is the market big enough to justify all the expense and production complication?"

I got the feeling that the MGB GT V8 would be manufactured, in the main for Britain, and the European Common Market. At this stage I could obtain no hard and fast statement on whether or not Australia would receive this latest 'Safety Fast' product. No UK prices are available as I write this story, but it is expected it will sell in the region of £2400 - say, (Australian) $4700.



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