All the Way from A to B: The History of the MGB, Part Two

THE RUBBER-BUMPER B

While the V8 came and went, a second intended MGB successor, known internally as ADO21, also failed to make production. Styled by Harris Mann and Paul Hughes of the Austin-Morris design office in Longbridge, the ADO21 was a wedge-shaped, mid-engine coupe with fashionable “flying buttress” sail panels. It was to have had a De Dion rear suspension and a choice of three engines: the 1,275 cc (78 cu. in.) A-series four from the Mini Cooper 1275GT, the new 1,748 cc (107 cu. in.) E4, or the 2,227 cc (136) E6. The smaller engine would allow the ADO21 to succeed the Spridget and Triumph Spitfire, but the six-cylinder E-series engines would have made it a credible successor to the MGB and MGC as well. Had the car made it to production, it might well have been called the MGD.

British Leyland’s enthusiasm for the ADO21 gradually diminished throughout 1970. The main problem appears to have been cost. Although the ADO21 used or adapted many components from other Austin Morris products, it would probably have been significantly more expensive to build than the MGB. Moreover, British Leyland’s market research showed that the vital American market strongly preferred conventional engineering. The ADO21 was finally canceled in late December and the prototype was scrapped about a year later.

(Some sources suggest that the ADO21 lost an in-house competition with a Triumph design that later became the TR7, but author David Knowles says that was not the case. The TR7 did indeed emerge from a design contest between Austin-Morris and Triumph, but while the Austin-Morris entry — also styled by Harris Mann — was badged as an MG, it was not the ADO21, which had died months earlier. Roy Brocklehurst, who succeeded Syd Enever as MG’s chief engineer in 1971, felt that the ADO21 did influence the TR7, but its impact, if any, was stylistic rather than mechanical.)

1974 MGB GT front
The 1974 MGB’s rubber overriders — nicknamed “Sabrinas,” after a well-known, buxom British actress of the fifties — added about 6 inches (152 mm) to the B’s overall length. North American models were now down to 78.5 horsepower (58 kW) due to a lower compression ratio and other changes for EPA emissions certification. This was the final year for the U.S. MGB GT; the hatchback coupe was withdrawn in early 1975, although it remained on sale in the UK.

With the collapse of the ADO21 project, the four-cylinder MGB soldiered on. If it had continued unmolested, that might not have been so bad, but the latest American safety standards made that impossible. Starting in 1973, U.S. regulations required bumpers capable of withstanding a 5 mph (8 km/h) frontal impact and a 2.5 mph (4 km/h) rear impact, increased the following year to 5 mph (8 km/h) both front and rear. By 1975, the bumpers also had to absorb that impact without any damage to the body structure or frame. It was an extremely challenging requirement, especially for cars that had been designed more than a decade before the standards were even conceived.

Since failure to meet the new requirements would force the withdrawal of the MGB from the American market, the engineers at Abingdon worked frantically to find alternatives. As a stopgap, early 1974 MGBs added comically large rubber overriders to the existing bumpers. These were replaced late in the year by completely new steel bumpers with conformal plastic covers to integrate them with the shape of the body. This was arguably a more satisfactory solution than the massive chrome battering rams of many contemporary Detroit cars, which would have been disastrous on the MGB. The new bumpers’ aesthetic impact probably would have been mitigated if they had been body-colored, like those of the later Porsche 924 and 928, but they were available only in flat black, which gave the B a somewhat unfinished appearance.

1974 1/2 MGB roadster bumper
The late-model MGB’s “rubber” bumpers are really hollow polyurethane shells concealing the beefy steel structure that provided the actual impact absorption. A wire screen behind the air intakes protects the radiator from debris. Unlike the earlier recessed grille, which was imposed by British Leyland, the new bumpers were developed by Abingdon under the supervision of body engineer Jim O’Neill, who later defended the rubber bumpers as the best available solution to a very difficult problem.

At the same time, the four-cylinder MGB was raised about 1.5 inches (38 mm) to comply with new U.S. bumper-height requirements. This wreaked havoc on the B’s center of gravity, compounded on roadsters by the deletion of the front anti-roll bar, apparently as a cost-saving measure. The result was substantial body lean and a much tipsier feel than earlier MGBs, only partially mitigated by the belated standardization of front and rear anti-roll bars in 1977.

The redesigned bumpers also contributed to the MGB’s burgeoning curb weight, which was beginning to approach that of the old MGC. That was bad enough for unrestricted British cars, but North American Bs had to be detuned significantly to meet federal emissions standards, losing their dual exhausts and trading their twin S.U.s for a single Zenith-Stromberg carburetor. Power ratings quietly disappeared from MG’s advertising and brochures.

While the motoring press averted its collective eyes, these various indignities had surprisingly little impact on the MGB’s popularity. Business was down from its early-seventies peak, but the B was still good for between 20,000 and 30,000 sales a year, comparable to its mid-sixties volume. The MGB had outlived several direct rivals and few of the ones that remained were in significantly better shape. The late “rubber-bumper” B had become a sort of aging diva — no longer as trim, pretty, or graceful as it had once been, but still sustained by the loyalty of its many fans.

1979 MGB roadster rear
We suspect that body-colored bumpers, like the “Elastometric” bumper covers that Chrysler offered on the 1970-1974 Plymouth Barracuda and Dodge Challenger, would have done wonders for the appearance of the late-model MGB. Unfortunately, Abingdon was unable to find a sufficiently flexible paint; none of their experiments proved durable enough for production. A proposed facelift of the MGB, known internally as ADO76, would have offered bumpers molded in different colors, but that project never came to fruition.

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  1. Excellent article …as usual!!

    Interestingly, the MGB seems to never die! Nearly all new parts are still easily available at surprisingly reasonable cost from companies like Moss Motors.

  2. I think Jetronic is a Bosch trademark–or did Lucas plan to take out a license from Bosch?

    Sounds like British Leyland had the same problem with the per-body fee for the B that Hudson did with the Jet.

    1. [quote]I think Jetronic is a Bosch trademark–or did Lucas plan to take out a license from Bosch?[/quote]

      They did. The system Lucas created for the O-series MGB was essentially one third of the system used in the contemporary Jaguar XJ-S V-12, which was a licensed version of Bosch’s D-Jetronic.

      [quote]Sounds like British Leyland had the same problem with the per-body fee for the B that Hudson did with the Jet.[/quote]

      Yup, a similar situation.

  3. [quote=Administrator]The system Lucas created for the O-series MGB was essentially one third of the system used in the contemporary Jaguar XJ-S V-12, which was a licensed version of Bosch’s D-Jetronic. [/quote]
    Even this shows how sadly "behind" BL was. The original D-Jetronic system first appeared on the 1968 VW Type 3 cars, and by the mid-1970s was already on its way out. The much simpler electro-mechanical (as opposed to electronic) K-Jetronic system was in common use from 1975 onward, and even that was in the process of being replaced by the fully electronic L-Jetronic system by the time the O-series engine was intended to be released.

    1. [quote]even that was in the process of being replaced by the fully electronic L-Jetronic system by the time the O-series engine was intended to be released. [/quote]

      This is also true, although Andrew Bywater of AJ6 Engineering notes that part of the motivation in using the older system was probably a desire for greater reliability. If you’re going to build something under license, I suppose it makes sense to choose a product that’s a well-known quantity with a substantial service history. Bosch may also have offered a significantly better deal on the D-Jetronic system than their brand shiny new L-Jetronic, which would have been attractive to cash-strapped British Leyland.

  4. In another example of BL’s horrendous management, Pressed Steel-Fisher, the MGB’s body supplier, had been a wholly-owned subsidiary of BMC/BMH/BL since 1965. In fact, it was BMC control of Pressed Steel that pushed William Lyons into the BMH merger, fearing threatened by having Jaguar’s bodies produced by a direct competitor in the luxury arena.

    All it would have taken was a few strokes of the accountant’s pen to write off PSF’s tooling investment and supply MG in a normal internal fashion. BL would have taken a small, immediate accounting charge, and the B would have been more profitable for the remainder of production. Either an example of a general lack of interest in MG versus Triumph, or total incompetence.

    1. I talked a little about the Pressed Steel/Jaguar situation in a sidebar in the article on the E-type Jaguar. I don’t know how threatened Sir William felt by BMC’s buyout of Pressed Steel before Donald Stokes offered a merger with Standard-Triumph later that year. The number of BMC products that competed directly with Jaguar was still relatively limited — the Vanden Plas Princess 4-litre R, perhaps the big Healeys — but Sir William decided that if he merged with Standard-Triumph, BMC’s principal rival, there was a strong chance of retaliation. According to Keith Adams, Sir William also looked at the merger craze spreading through the industry and realized that if Jaguar were acquired, it might not be by his choice. In that light, cozying up to BMC seemed prudent, and it certainly allowed Jaguar to retain more of its identity after the merger.

      I’m not an accountant, and my knowledge of British law is limited to the viewing of the odd BBC drama, so I have no idea what kind of fiscal implications would have been involved in restating or writing off the tooling costs; that probably would have been an additional concern.

      I suspect the real problem was finding someone in a position to actually authorize it. One of British Leyland’s biggest problems was its sheer size — more than a hundred different companies, with offices and factories scattered throughout the UK. (The fact that many of those companies had recently been bitter rivals certainly didn’t help.) If something involved multiple divisions, it almost certainly had to be authorized and supported by someone quite high up the food chain; I assume neither MG, Austin-Morris, nor PS-F had the authority to make such a change. By most accounts, senior BL officials were often quite overwhelmed by the scope of their responsibilities, and it was easy for that kind of relatively minor accounting detail to be lost in the shuffle. That in itself wouldn’t necessarily be a sign of either incompetence (except insofar as it reflected the inadequacies of BL’s management systems) or favoritism. There are instances where the latter was clearly a primary factor (like Lord Stokes’ instance that the winning Austin-Morris design in the corporate sports car competition should be built as a Triumph, not an MG), but I think the larger problem was that BL was so unwieldy and its executives spent so much time doing triage that the forest was often lost for the trees.

  5. Hi and thanks for a very interesting read. I read about the MGb O series a little while ago and was lucky enough to get my hands on an O series engine complete with twin carbs from an SD1. After a little fettling I mated it to a standard B box. The car pulls extremely well and is very capable against modern cars. If I could do it with just a few hobby tools and a small workshop then why on earth BL did not try it is beyond me. Thanks again Mike.

    1. In some ways, swapping an engine into a single car is simpler, because you can just keep fiddling until it works properly. Certainly, there’s a lot less paperwork! It wasn’t that fitting the O-series was a great technical challenge, it’s that it required a commitment of engineering resources, including adapting the Lucas Jetronic injection system for the U.S. cars and going through the various certifications for crash testing and federal and California emissions standards, including the EPA’s 50,000 mile (80,000 km) durability tests. The irony is that BL did ultimately do much of that work, only to cancel it at the last minute anyway.

    2. I’m interested in your O Series conversion. Could you send me your email address as I have a few questions…..cheers Rob

  6. Hello Aaron,

    let me first of all congatulate you with your fantastic website: it is very nice indeed!

    Secondly I am very pleased with the picture you put in it.

    For fun I also gave you the webadress to have a look on some more pictures of my car.

    Best regrds,

    Axel Volker
    Leusden, the Netherlands

  7. great article. Is it correct to say that only 1,000 1980 Mgb limited edition were shipped to the USA.

    1. No — the 1,000-unit figure was for the British-market Limited version that closed out production. I think there were significantly more than 1,000 U.S.-market Limited Editions.

  8. I’m sorry it took me five years to come across this, but I was very interested to see the thread about Jim Stimson, who used to work for Syd Enever but had started off at Cowley. Jim was always insistent that he had drawn up a coupe MGB with a higher roof but that when Syd Enever showed the result to (I assume) Harrimann, he was told to ship a roadster and his drawings out to Pininfarina. I have to say that other former colleagues of Stimposon’s were often unsure of what had happened (they weren’t necessarily involved in some of the forward prototype work, and Stimpson worked in the Boilerhouse at Abingdon, away from prying eyes) but Jim was quite assertive about it, and I wrote more in my recent “MG V8” book. Stimpson also claimed detailed authorship of the long nose used on the MGB at Le Mans.

    1. If he did come up with the idea first, I can certainly understand his exasperation with seeing it attributed to Pininfarina! I’ve seen various examples in other organizations in which ideas are suddenly taken more seriously when an outside consultant says them, even if the consultant is really just repeating things the staff have said or suggested previously. While I obviously don’t know for sure if that was the case here, it certainly happens often enough to seem plausible.

      1. I should perhaps clarify the point about Pininfarina; their work unquestionably transformed the MGB GT into the good looking car that it became – even Jim Stimson was keen to acknowledge that. Sergio Pininfarina personally told me that in his opinion, the MGB GT was the best looking design for BMC that came out of his company. Meanwhile those interested in the story have looked for more evidence; suffice to say I have found some, and it will be in my next MGB book, due for publication in 2020…

  9. Does anyone have any info on the missing MGB Targa. Its not mentioned here and Im trying to gather up info on the car to be able to build one. I have been hunting photo’s and to date have 5 and 2 newspaper article, thats taken 2 yrs. I have all the google stuff. but anything else would help, thanks.

    1. Do you mean the Jacques Coune Targa?

  10. I had a 1971 MGB GT which I purchased 18 months old from a daughter of the President of the Ferrari owners club. I was told it was one of 6 made in Italy by Alfa Romao who were going to build them ( under licence) but then the agreement fell through for some reason.
    Not sure now whether story was true or just sales talk by owner.
    However it did have an aluminium bonnet & boot lid. I put a Downton conversion on it that made it quicker than a friends MGC
    Sold it in 1976 due to arrival of 2nd babs. Great car !!

    1. Without some kind of documentary evidence, my inclination is to be skeptical of the story. BMC did of course have various local production deals, some in Italy — see also the Innocenti Mini — but I have a hard time seeing why Alfa Romeo would be interested in building the MGB GT, which would have competed with the Alfa Giulia Sprint. Also, by 1971, British Leyland was expecting the MGB to expire in the near future, replaced (along with the Triumph TR6) by the Triumph TR7. The auto industry is full of weird deals, so if somebody says, “No, no, funny story, but it’s true, look at this evidence,” I’ll take that, but my off-the-cuff response is, “That doesn’t sound right at all…”

      1. I agree. A good pub yarn without any hard evidence. Reminds me of the ‘genuine factory MGB Daimler V8’ which I found was no such thing. Last known in Switzerland in the ownership of someone who probably didn’t like discovering the truth.

  11. looking for my 1968 MGB red with black and red interior. with 6 cylinder Capri engine

  12. It is interesting to note that unlike the MGC and stillborn Big Healey version, an attempt was belatedly made to differentiate the MGB GT V8 Coupe from the MGB sometime in the early/mid-1970s though coming came of it, via a clay mock up on page 147 of David Knowles – MG: The Untold Story book with the overall shape intended as a sort of “junior” Jaguar XJ-S and the front end even featuring a Jaguar-like nose (though the lack of grille on the clay mock up is almost reminiscent of the Bristol Blenheim 3S/4S).

    1. Yeah, the MGB story is littered with interesting ideas — some perfectly reasonable, some perhaps a stretch under the best of conditions — punctuated by a lack of money and a low place on the list of corporate priorities.

      1. Indeed. Read also in same book of Aston Martin proposal eventual rebodies of the MGB had they been successful in acquiring the MGB from BL.

        Despite already being considered a success the MGB has always come across as a compromised design, due to neither featuring IRS let alone a 2-litre+ engine from the outset which could have further prolonged its production without the 13 year gap between the MGB and MG RV8.

        Could an MGB plus derivatives receiving the sum of proposed improvements have made it even more of success where outside of the occasional rebody or few, there is less of a need to replace it until a proper successor is developed?

        ADO21 was unviable outside of the styling which was used for the TR7 and the Healey WAEC needed a more potent engine, while the EX234 was a Midget replacement that could have taken over from the 4-cyliner MGBs (the latter featuring 6-cylinder / V8 engines), been updated with R6 Metro-type interconnected Hydragas (think front-engined RWD MGF predecessor) as well as carried over the styling of ADO21.

        1. The question is not so much, “Could the B have been improved or modernized to good effect?” — the answer to that is indubitably “yes” — but, “Would it have made a commercially meaningful difference?” The MGB was basically a late ’50s design soldiering on through the sales inertia granted the gradual extinction of most rivals. It was not unlike the position the Mazda MX-5/Miata has occupied in more recent years, where it had an obvious niche that was sustainable, but only so long as there was not a lot of direct competition. That niche was not about the MGB being a modern car or even a particularly good one by ’70s standards (much less ’80s ones), but about it being a cute small roadster for a not-horrendous price. Would customers, particularly American ones, have welcomed a bit more power and a less choppy ride? Sure. Would those qualities have persuaded more people to buy an MGB? I’m inclined to say probably not.

          I don’t doubt the MGB could have continued soldiering on through much of the ’80s had Aston Martin continued production, but my suspicion is that the more ambitious proposals would have ended up falling by the wayside because Aston was not exactly flush with cash and sooner or later someone would have done the math and grasped that the extra expense would just make the car less profitable (or possibly a money-loser) rather than more successful.

          Periodically of late, I see late-night TV infomercials for various skin creams that are supposed to fill in lines and hide wrinkles and baggy skin. The demonstration phase of those infomercials shows that, at least under those selective conditions, the cream or remedy does temporarily mask certain lines and create the appearance of smoother skin. What it does not do, and could not do, would be to make the subject look younger. Does a 70-year-old with four sets of visible creases around his eyes look better than one with six or eight sets of creases? Arguably, I suppose, but I’d be hard-pressed to say the reduction in wrinkle-count makes him look less than 70.

          As a separate matter, I don’t think history has validated the merits of Hydragas. Even the MGF, much more modern than the proposed MGB successors/evolutions, did not demonstrate any particular ride or handling advantage over a well-tuned conventional suspension, certainly not enough to justify the cost and repair/replacement issues. There is a tendency to throw technology at automotive suspensions when something less elaborate would serve as well or better if the designers would hire some competent chassis tuning experts who can properly sort the balance of springs, dampers, bushings, and tires. It’s only been quite recently, in a historical sense, that features like adjustable shock absorbers, air springs, or active anti-roll bars have become more than just a costly brochure gimmick, and I can’t help suspecting that they’d be less worthwhile if not for the modern fad for giant, heavy wheels with ultra-low-aspect-ratio tires.

          1. While an argument can be made about the merits of Hydrolastic / Hydragas (IMHO its potential was constrained by BL’s financial problems and was said to work very well in both the Rover Metro/100 and the Minki-II prototype), EX234 does give an idea as to how the MGB could have been replaced.

            Essentially EX234 would replace both the Midget and the MGB featuring 1300-2000cc 4-cylinder engines, with an upscaled 6-cylinder and V8 version replacing the MGC / GT V8. Meanwhile the gap below EX234 could be filled by the Mini-based prototypes like ADO34 (plus ADO35/ADO36) and ADO70 featuring 1000-1300cc engines.

            You are probably correct that such models (sans Mini-based sportscars) would likely feature conventional (ideally all-independent) suspension, OTOH it is possible there would be two different versions depending on which side of the Atlantic they are sold at.

            In terms of suitable styling for the 1970s and beyond it is a dilemma, the Pininfarina styling of EX234 needs more work IMHO though quite like the look of the ADO21 (particularly at the rear) sans rear flying buttresses and pop-up headlights though a composite of the former with the styling of the Rover SD1 (particularly at the front) could work (especially since the latter was such a departure for Rover from the P6 in the same way the TR7 was for Triumph from the TR6 with both SD1 and TR7 styling actually being better suited for MG).

            As for the MGB itself would have been content with it receiving a 106 hp 2-litre B-Series (possibly even a 112-115 hp 2-litre B-OHC), IRS as well as either a 2.4-3-litre B-Series 6-cylinder or a properly-developed (and significantly lightened) C-Series for the MGC prior to gradually being replaced by the early/mid-1970s. One could make a case for a reliable properly developed version of the MGA’s 1.6 B-Series Twin-Cam engine that grows to 2-litres and spawns inline-6 variants, yet the Twin-Cam was still likely to be a limited-run engine as opposed to a genuine productionized challenger to the Alfa Romeo Twin-Cam.

          2. Well, as the article says, BL did the work on putting the 2-liter O-Series in the MGB, although that didn’t come to pass.

            I don’t know that the EX234 would have found a strong market. It had its interesting points, but Bruce Williams’ remarks about the American market also applied. The Toyota Celica (q.v.) ended up being more what U.S. buyers wanted in a sport coupe; it was uncomplicated (and the U.S. didn’t get the twin-cam or injected versions), economical, affordable, and well-built, which went a long way toward making up for its lack of verve.

          3. That is true. However BMC did look at a 106 hp 2-litre B-Series OHV a few times during the early/mid-1960s, yet by the time they actually considered putting a 112-115 hp 2-litre B-OHC into production it could not be built due to the tooling being past its prime.

            Am not 100% sold on the EX234’s Pininfarina styling though it could have potentially had a fairly long production life due to being more sophisticated compared to both the Midget and MGB as well as indirectly taking over from the original Lotus Elan (prior to the original Mazda MX5). Cannot say whether EX234 would have would spawned a 2+2 GT coupe or even have enough room in the engine bay for the Rover V7, yet would not be surprised if either is the case.

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