Concepts and Prototypes : Triumph Broadside (1979-1981)

Was the Triumph Broadside one of the biggest missed opportunities of the British Leyland era? It was designed to take the best bits of the TR7 it was based on, and sling out the bad bits to create the perfect sports car for the US market.

However, events overtook it and, just at the point it should have been readied for production, it was cancelled – and with it went the future hopes and dreams of Triumph.

Broadside: sports car revival scuppered before launch

Triumph Broadside

The Triumph Broadside could also be known as son-of-Triumph Lynx. This was a last-ditch attempt to spin the Triumph TR7 into a viable range of cars. Broadside was designed to be sold in US-friendly MG and Triumph versions powered by a Federalised version of the O-Series engine, as well as an injected Rover V8.

The thinking behind Broadside was solid enough. Rover-Triumph Engineers had worked on several versions of the Triumph TR7’s platform in a variety of wheelbases, taking in the four-seater Triumph Lynx and MG Boxer (RT078) sports car, the Triumph SD2 hatchback and the Marina-replacing TM-1 programme. By the time the sleeves were rolled up to work on Broadside, Rover-Triumph knew exactly what it was doing with the simple, scalable TR7 platform.

So, what was Triumph Broadside?

In a nutshell, the Triumph Broadside was a coupe and roadster pairing based on the Triumph TR7, but with a lengthened wheelbase, updated interior, the passenger doors from the Lynx, and new rear-end styling. In early 1979, the brief was laid out under the project code RT061, and work began on creating the new coupé and convertible.

The first mention of the car appears in the 1979 Jaguar Rover Triumph Product Plan, where it was known initially as the SC1 (Sports Car 1). A ‘phased introduction’ was planned for the a pair of cars, initially designed to replace the Triumph TR7, but also to form the basis for the MGB and Midget replacements.

Even as this point, ‘a high level of common mechanical components’ would need to be shared. At this stage, the smaller version, powered by a 1.7-litre O-Series engine was mooted for a Autumn 1983 launch, with the larger 2.0-litre sports car arriving in the autumn of 1984. All SC1-coded cars would be designed to conform with EEC and North American legislative requirements.

What were the Broadside’s biggest obstacles?

For the long-term survival of MG and Triumph in the USA, there was no question at this point that both marques needed to represented by the new model range. Styling certainly looked good, with an agreeable mix of TR7, SD1 and Lynx in its DNA, but a whole lot more balanced, too – especially in 2+2 convertible form.

The coupe Broadside was a little more compromised, with a truncated rear that didn’t marry well to the wedge-like front-end. Towards the end of 1979, Italian design house Michelotti was asked by David Bache’s flat-out Design Team to restyle the car – and promptly produced a sleeker, less TR7-like front end. At this point, it’s clear that the project had the style and appeal to succeed.

Triumph Broadside
Michelotti’s take on the Broadside concept can be seen in this picture. The Italian styling house’s version was sleek and stylish on paper… (Picture supplied by Achim Küpper)
Triumph Broadside
Broadside convertible under construction at Canley (Picture supplied by Achim Küpper)

How the Broadside developed into 1980

By the time the newly renamed Rover-Triumph 1980 Product Plan was unveiled, there was certainly more flesh on the bones of the Broadside project. Notwithstanding the spring 1981 launch of the MG Boxer to replace the MGB and MGB GT and the autumn 1981 arrival of the O-Series-powered TR7 to replace the existing slant-four, the launch date for Broadside was brought forward to spring 1983. Plans for a 1.7-litre Broadside were dropped at this point.

According to the product planning document, the Broadside was a direct replacement for the TR7/TR8 and short-lived MG Boxer. It was very much shaping up to be a new-looking sports car based on existing hardware, and a new intermediate wheelbase, stretched by five inches over the TR7.

Interestingly, at this point, Broadside’s life was mapped ahead of it:

  • Autumn 1984 Electronic instruments introduced
  • During 1985 Engine updates to meet emissions requirements
  • During 1986 Engine updates to meet emissions requirements
  • Autumn 1987 Runout models: Dependent on the future possible opportunity of developing a new car in collaboration with Honda, together with a successful launch
  • Possible opportunities on base plan
    Dependent on Austin-Morris engine strategy, an opportunity exists to install a turbocharged version of the O-Series from the introduction of the Broadside.

Engine issues and project struggles

Triumph Broadside
Triumph Broadside Coupe was a rather unhappy-looking thing – reflecting the fact it was based on the Lynx, which was also rather compromised

Tony Cooke worked on the Broadside’s O-Series engine conversion for BL, and it wasn’t an entirely happy experience. ‘Somewhere else in the back of my mind is an image of a sunny afternoon at Fletch North engineering,’ he said.

‘I was told O-Series would not pass North American emissions specification, and the project was cancelled. We had just wasted months. Bad feelings like that are hard to quantify.’ – Tony Cooke

‘I was working on the TR7 O-Series and was just checking out a car for finalisation of the cooling system, outside in the car park. Then a more senior manager came up to me and told me the news. The O-Series would not pass North American emissions specification, and the project was cancelled. Stop right now. Apparently that it would not pass had been known even before the fit was suggested. We had just wasted months. The bad feeling events like that generated are hard to quantify.’

Triumph Broadside
The O-Series engine in the Triumph Broadside – rendered impossible thanks to its inability to meet US emissions regulations

Triumph Broadside: death comes swiftly

Unfortunately, along with such projects as the AM2 (Metro saloon) and Princess estate, the Broadside project was cancelled by BL management. This decision was a difficult one, borne from interest rate changes that had made exporting cars to the USA unprofitable – thereby killing the benefit from the Broadside’s largest sales market. The closure of Speke, Abingdon, Canley and – ultimately – Solihull also meant there was no longer production capacity.

In addition, BL was in meltdown by 1980 and the simple fact was that the only finances being released to the company by the Government were going to be channelled into the development of the LC8 and LM10. Anything else on the agenda was too low down in the list of priorities and so was cancelled – in a stroke, closing off the company to the US market after years of strong sales in the sports car market.

The formation of the Light Medium division in 1980 put an end to the idea of Rover-Triumph design and development autonomy – and ended any chance of continuing in the sports car business. It would take until the mid-1990s, and the arrival of the MGF, before the TR7 and MGB were replaced – a tragedy in itself.

Triumph Broadside
Triumph Broadside
Keith Adams


  1. The DHC certainly looked good. Like a mini Stag. Was it a 2+2 like the coupe? Pictures seem unclear but I suppose small TR4-like rear seats were possible, if not very practical. Coupe is TR7-SD1 hybrid that does not work.

  2. As usual BL put the screws to anything that came out of BMC. In the long run Leyland screwed themselves. No matter what sports car they were going to come up with could never hold a candle to the Datsun 240Z and the successor 260 and 280 and 300 series.

    • The 240Z was a distinguished car , the 260 less so and the 280 and 300 were eminently forgettable . Yet another example of the fact that you cannot improve upon a really good idea , and that attempts to do so usually result in going backwards

      • Yes, the 240Z original was the most revered car in the Z range. In 1979/80 when I bought a humble Datsun Cherry, my aspirational car was the 280ZX, though by that time it was considered a sports tourer (2.8 6 cylinder motor putting out 140bhp) – seemed powerful in those days.

  3. Several mentions in this piece of the MG Boxer, which I’d not come across before. Is there any more info or pictures ? I can’t find any other references to it anywhere.

  4. AFAIK a few pictures of the MG Boxer appear in Google search under “MG TR7”, more info though regarding the MG seems to appear in MG – The Untold Story by David Knowles

  5. I think the missed opportunity was that the “simple scaleable TR7 platform” wasn’t used for a mid 70s Marina replacement to fight the Mk3/4/5 Cortina. Sounds like this would have been a relatively simple job to produce a midrange car with platform economies of scale that would have sold in far greater numbers and more profitably than expensive blind alleys like the 18/22 Princess.

  6. And if the O Series couldn’t be federalised couldn’t the slant 4 have soldiered on? Possibly sharing some of the development work Saab was doing on this unit.

    • If you look at Saabs development of the engine, and later the block itself the engine had huge potential to carry on as the groups mid range engine, but as ever Leyland couldn’t see the wood from the trees, and instead of a focused plan we got a hotch potch that failed to deliver.

  7. A real shame that BL abdicated this sector as with the pound weakening and the economy recovering their range by the mid/late eighties really could have done with a premium product, something to keep a bit of glamour in the showroom. And in Abingdon they had the perfect factory to build such vehicles.

    Puzzled why the O series engine couldn’t pass US emissions tests, when the engine would last well into the 90s in the UK, by which time surely UK emission requirements would have been as tough as the US ones in 1980?

    • Abingdon? The perfect factory? Clearly, you never went there. It was little more than a CAL line and car storage depot. The place was tiny, and utterly unsuited to car manufacture.

    • By the 1990 electronics were much more advanced than in the 80’s and the experience to smogify engines was much deeper. There would have been step changes along the way rather than one big leap from little to no emissions to federalized smog tests.

  8. The Broadside would have been the answer to the issue of the ageing MG models and the less than sucessful TR7, and would have kept the Triumph name alive for longer. However, it was a niche product, British Leyland seemed to be on the verge of collapse at the end of the seventies, and what money was available was needed for the M cars. By 1981 all the MG and Triumph sports cars had gone anyway and a recession in America and a strong pound mad exporting British sports cars too difficult.

  9. How was Broadside or SC1 (Sports Car 1) supposed to form the basis for an MG Midget replacement?

    The 1.7 O-Series would be too large (and relatively underpowered) for a Midget replacement that would have likely utilized the 1.3 A-Plus (including Turbo) and 1.6 S-Series (plus possible Turbo) engines, like the fact this project appears to retain a front-engined RWD layout though one wonders if the Midget replacement was instead planned to instead feature a mid-engined RWD layout similar to the MGF-like Metro-based Towns TXC Tracer.

    Perhaps this project is also the origin for Michelotti’s Midget replacement proposal design which was later recycled (albeit unfinished) into the Reliant Scimitar SS1?

    • I was thinking the MGB, which used the 1.8 B series and was MG’s biggest selling car. The Midget and its Triumph Spitfire cousin would probably have gone in the rationalisation that saw the bigger Triumph Broadside become British Leyland’s principal sports car. Remember, the MGs and the Spitfire were old designs by 1979/80 and lacking performance, a 1.6 litre Capri could probably keep up with a Spitfire by 1979.
      I think the Broadside could have gone ahead if British Leyland were willing to gamble on the car’s success. The TR7 was still selling OK when it was axed in 1981 and the quality was much better on later cars, so it’s likely there could have been a large market for the new car, and America’s economy began to recover in late 1982 and then boom for the rest of the decade, which would have ensured healthy export sales. Yet it wasn’t to be.

      • While there is appeal in replacing all sports within the range from the Midget/Spitfire to the B/TR7 with one model, the mention of a Midget replacement or “Broadside Junior” would suggest the simple scaleable TR7 platform was also capable of being scaled down further to something comparable to the later Mazda MX-5 or Reliant Scimitar SS1 in terms of dimensions and weight.

        Unlike the MG Metro Turbo, an Midget replacement carrying over the same engine would be able to produce more power (around 120-130 hp) thanks to not being limited by the in-sump gearbox.

        Given the Scimitar SS1 featured a 1.3-1.4 CVH it would not have been unusual for “Broadside Junior” to carry over an updated MG / Cooper S spec version of the 1.3 A-Plus at the bottom of the range though it seems more likely for “Broadside Junior” to solely feature the 85-103+ hp 1.6 S-Series (including a turbocharged variant capable of as much as 150 hp).

    • That silhouette does look SD1 shaped, makes you wonder what the Triumph team thought when they saw Rover bring a similar design to the competition

  10. What was the limiting factor that prevented the O-Series from passing US emissions standards despite it being conceived for pretty much that reason, was it something about the constrained O-Series design itself or something that could have been resolved under better financial circumstances with some early 16-valve Twin-Cam M-Series precursor?

    Even if the existing Triumph Slant-Four was said to have been signed off for Federalisation until 1986 it was obviously not realistic to continue to use it solely for Broadside (nor could it fit into the MGB despite enthusiasm for the idea by MG), which leaves just the Rover V8 as the only engine option for the US though IIRC it was claimed in one book on the TR7 (by David Knowles) that the company looked at a cut-down V6 version of the Rover V8 for the stillborn Rover Bravo project that would later tie into the MG Metro 6R4 story before the latter received the bespoke 3-litre V6.

    TBH GM did pretty well with the Buick V6 once they bought back the tooling and manufacturing line from AMC, yet even they had to update/redesign the V6 twice in 1977 and 1988 to fit a split-pin crankshaft, balance shaft and on-centre bore spacing – where the left-hand bank of cylinders was moved forward relative to the right-hand bank as well as use of a 3x/18x crank-trigger system and other improvements for its potential to be unleashed. Did Rover later BL possess a similar capability to resolve the issues an all-alloy Rover V8-based V6 would have likely faced had it been approved for production?

    It is fascinating to compare the O-Series (and later M-Series) with the distantly related yet similarly-displaced Nissan CA that was able to meet US emissions standards even in 8-valve SOHC (via NAPS-X) and like the O-Series with the Perkins / L-Series, would also spawn a dieselized version as the Nissan CD.

  11. Why wouldn’t you introduce the V8 first? It would provide a halo for the car and glowing reviews as that’s what the magazines would get – then bring in the lower end once it’s established as a true sports car and make it affordable. What they were doing was making sure the first reviews would have been lackluster – strange thinking as in so many situations by BL.

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