It’s Not V, It’s U

The Bagheera’s highly unusual twin.

In the early 1970s Automobiles Matra enjoyed popularity as a manufacturer of relatively inexpensive light sportscars such as the Djet, 530 and Bagheera. The French firm’s racing arm – Equipe Matra Sports, founded in 1965 – likewise had swiftly built up an impressive palmares in motorsports. Matra won the 1969 Formula One Championship with the MS80 driven by Jackie Stewart and with the MS670 emerged the overall victor at the gruelling 24h Le Mans endurance race three years in a row starting in 1972.

These impressive results stimulated Matra to entertain the idea of adding a faster, more powerful sportscar to the range to capitalise on the motorsport successes. Initial experiments where the 530 was fitted with the 2.3 Litre Ford V6 and later the 1.8 Litre inline four of the new Chrysler 180 proved dead ends and were abandoned early on.

Project 550, which was to become the Bagheera in 1973, soon took precedence. Powered by the 1.3 litre engine of the Simca 1100 Ti, this modern mid engined sportscar with its interesting three-abreast seating arrangement was originally also to be joined by a much more powerful eight cylinder version internally known as project 560.

Restoremania.motards.net

Matra engineers Philippe Guédon and Georges Pinardaud had devised a most unorthodox engine for the planned flagship model: an eight cylinder engine, but not in the traditional V configuration nor as an outdated inline straight eight. Their engine concept was so unusual that it warranted a new name: U8. The U8 consisted of two different Simca engines: one the same 1294cc four as fitted to the standard Bagheera, the other also a 1294cc four – but this was the version that powered the rear engined Simca 1000 Rallye 2 whose crankshaft turned in the opposite direction.

Encyclautomobile.fr

The engine blocks were positioned against one another at an angle of 82° and worked independently of each other – they had separate ignition distributors and valve gear as well as their own petrol, water and oil pumps. For the coupling of the crankshafts, a common crankcase with gear connection was fitted.

At the front of the first engine, a sprocket and Morse chain connected the crankshaft to a central shaft and another chain provided the connection with the other crankshaft but this time to the back. The other engine received the flywheel, a diaphragm clutch and a 5-Speed Porsche-sourced gearbox. A self-locking differential was to be part of the setup.

R. Muller

Being substantially larger, it was no longer possible to mount the U8 engine transversally as was the case with the normal Bagheera, so the U8 was mounted in a longitudinal configuration. As a result of this the wheelbase had to be stretched by 9 inches, to 102 inches. The rear suspension was changed to a double wishbone setup and ventilated disc brakes were fitted on all four wheels to cope with the extra grunt.

Inside, a more comprehensive instrument panel with separate gauges for each engine was the only noticeable change. The 2588cc U8 developed 168 Bhp at 6200 Rpm; this would put the U8 in approximately the same performance bracket as for example the Alfa Romeo Montreal which although more powerful was also heavier; Matra even had its eye on Porsche’s 911 as a possible target.

Top speed of the Bagheera U8 was 146 mph but its fuel thirst when driven to its maximum potential was reportedly a horrendous 8.4 Mpg. More development could and likely would have brought this down to a more acceptable level, but the projected sales price at which the U8 would be profitable presented another problem. Matra calculated the price of the U8 at around 65,000 Francs; in that same year one could drive away in a brand new BMW 3.0 CSi for 63,700 Francs while a Porsche 911 S carried a price tag of 69,000 Francs. Oh, and the Citroën SM seemed almost a bargain by comparison at 59,350 Francs.

Restoremania.motards.net

The energy crisis and Chrysler France’s own financial difficulties sealed the audacious but complex Bagheera U8’s fate – the project was shelved during 1974. Just three prototypes were ever built of which one has survived and is on display at the Matra museum in Romorantin. With the complexity of the unproven drivetrain concept in mind and the potential ensuing reliability issues it is probably for the best that the Bagheera was limited to a 1294cc four during its 1973-1980 lifespan; on the other hand… wouldn’t it be fascinating to know what a U8 sounds like?

Author: brrrruno

Car brochure collector, Thai food lover, not a morning person before my first cup of coffee

14 thoughts on “It’s Not V, It’s U”

  1. Good morning, Bruno and thank you for yet another wonderful read. I wonder why this particular setup was chosen. To keep development costs down? But then again the changes made to the car were substantial and resulted in an estimated price increase of roughly 40k FRF on the original 25k FRF of the standard Bagheera. At least that what I found this morning on a Matra site.

    I would definitely like to hear this engine. I imagine it would sound like a flat plane crank V8 but different.

    1. The U8 surely would have been world record holder for tappet noise – a thousand grannies in a knitting contest.

    2. “a thousand grannies in a knitting contest”…brilliant!

      I notice they also decided to reprofile the tail subtly and took the opportunity to change the tail lights for those ubiquitous Alfa Romeo items:

    3. Thanks Bruno. I have read before something about the U8 only in L´année Automobile, where they said the U8 would be a production model. I suppose the book was written just before the oil embargo.
      8.4 mpg is not great, but it beats the Robocop film “6000 SUX”!

  2. That engine sounds mad in a proper Gallic fashion, but if the creators had less loyalty to the rattly old Poissy in-line four, the principles are sound enough to lift the Bagheera to a higher level.

    Trouble was that Simca were in the wrong alliance at the time. Crumbling Chrysler – or even, at a stretch, Mitsubishi – had nothing useful in the way of engines and transaxles to offer the project. Previous partners Fiat and future owners PSA had the hardware to make it work around 1973-4.

    I wonder if the Matra designers gave a moment’s thought to trying the same trick with the bigger, and far better 180 engine.

    1. The Chrysler-Simca 180 engine was tried and found unsatisfactory. That’s why they originally didn’t want to use it in the Murena, but were forced to do it because Renault refused to deliver the Douvrin four to Matra.

    2. Had Chrysler thought of it sooner an 1960s LA V6 (possibly with a Slant-6 style all-alloy block and French equivalent of the Rotomaster turbocharger used by Bristol on the LA V8) could have potentially been an option. Another would have been a more flexible V6 in place of the Slant-6 decades before the (reputedly Slant-6 derived) 3.3/3.8 60-degree V6.

      Was of the understanding the Type 180 engine drew inspiration from the BMW M10 engine, with BMW themselves looking at an M10 derived V8 (and M30 derived V12).

      However Simca with their domestic market in mind (as opposed to outside of France) seemed to have no interest developing anything other than 4-cylinder engines, which also helped contribute towards the cancellation of the Chrysler UK developed Avenger-based 60-degree V6 engine planned for the 180 (another what-if option).

      Perhaps Matra could have collaborated with Jensen-Healey (who were keen on replacing the unreliable Lotus engine) on developing a 16-valve head for the Type 180 engine instead of pursuing their own separate 16-valve projects for the same engine (Jensen-Healey were working with Ricardo a 16-valve DOHC head for the 180)?

    3. Another would have been a more feasible 8-valve (if not 16-valve) OHC (?) development of the Poissy engine.

      http://www.speedhunters.com/2013/10/sonic-destroyers-v12-thing/

      From the above image and article – “This was another prototype engine, based on a Simca 16-valve four-cylinder. The 1.3-litre had a cylinder head derived from the F1 V12 programme, and made a handy 180hp; three engines were made, with the plan being to put this in the Bagheera, but Simca’s management refused, much to the car’s detriment.”

      Along with a production viable version of the Poissy Turbo engine used in the 1982 Talbot Horizon Turbo concept (in tandem with the above Poissy developments plus the improvements the engine would later receive under PSA).
      https://reallyloud.co.uk/2020/06/28/1982-talbot-horizon-turbo/

  3. What is this “mpg” that you speak of? I’m a European, I can only think in Metric.

    1. If only it were gallons per mile? Miles per gallon is an equation I have no use for.

  4. I love this kind of story, it speaks to the enthusiastic innovation which engineers and manufacturers adopted during the era in question. Thank for telling it so sweetly and pithily.

  5. I learned some new things here – there are shades of the Honda NSX having a complete redesign and reorienting the drivetrain from transverse to longitudinal, or even the Ferrari Mondial T – no change to the wheelbase & body though.

    There were some clear signs that they should have not proceeded any further in my view – it’s hard to make a case for the Heath Robinson engine arrangement (keep looking for alternatives), and when the wheelbase extension was brought up. I wonder when the projected sales price was arrived at? Surely that killed the project stone dead.

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