One Last Push (Part One)

Today DTW remembers Renault’s post-WW2 series of rear-engined cars.

1954 Renault 4CV Brochure (c)

The post-war worldwide success of the Volkswagen Beetle(1) encouraged manufacturers as diverse as Fiat, NSU, Renault, Rootes, Skoda, ZAZ and even General Motors to emulate its mechanical layout, with varying fortunes. In so doing, many appeared to miss the point that the Beetle was successful despite rather than because of its rear-engined layout.

A rear-engined design typically involves many compromises with regard to packaging for luggage space, engine accessibility and cooling, and handling and stability. The smaller the car, the less important these compromises are, but the layout becomes increasingly unviable as the design becomes larger and more powerful. Porsche spent the best part of sixty years engineering out the instability(2) caused by having a heavy weight mounted aft of the rear axle on the 911, while General Motors suffered huge reputational damage owing to claims of dangerous instability made about the rear-engined Mk1 Chevrolet Corvair.

During WW2, Renault was controlled by the occupying German forces and was under orders to build only military and commercial vehicles in support of the Third Reich’s war effort. Renault’s Director of Design, Fernand Picard, anticipated that, after the war, France would need a small and economical car to help remobilise the country. He led a small team that covertly developed what would become the 4CV.

There has been much debate as to what extent the mechanical layout of the rear-engined 4CV had been influenced by the VW Type 1. Renault was nationalised immediately after the war and its new chief executive, a fiercely patriotic former resistance fighter named Pierre Lefaucheux, was outraged by that suggestion, and even more outraged when the new French government asked Ferdinand Porsche to advise on getting the 4CV into production. Porsche received a hostile reception at Renault, then spent almost two years without trial in a French prison on unproven allegations of war crimes, allegedly at the behest of Lefaucheux.

In any event, the 4CV was unveiled in 1946 and entered production the following year. It was a rather pleasant looking small four-door, available in saloon and cabriolet versions. The latter was simply the saloon with a roll-back fabric roof. Later, a commercial version would be offered, although this was little more than a saloon with no rear seats and unglazed rear doors. The 4CV had a monocoque bodyshell and was 3.66 metres (12 ft) long.

1946 Renault 4CV (c)

Powered by a 760cc 17.5BHP inline-four engine mated to a three-speed gearbox, the car weighed just 620kg (1,370lbs) and was a sprightly enough performer to prove a bit tricky on wet roads, particularly with its light front end and highly geared steering, at just 2½ turns from lock to lock. Renault subsequently reduced the gearing to 4½ turns to reduce the risk of accidents.

Sales started slowly but picked up strongly as the French and European economies began to recover. The 4CV was exported widely and assembled from CKD kits in a number of overseas territories in order to avoid punitive import taxes. Total sales were 1,105,543 which made the 4CV the biggest selling French car to that date. It was nominally replaced by the Dauphine in 1956 but its lower price and specification allowed it to remain in production until 1961, when the FWD Renault 4 was launched.

As the post-war economic recovery gathered pace, Lefaucheux and Picard saw an opportunity to offer a larger and better appointed car than the 4CV. Development work began in 1951 on what would become the Dauphine. The exterior style was agreed at a relatively early stage in the process: recognisable prototypes were being road tested as early as 1952, some four years before the Dauphine’s launch.

Whatever the influence or otherwise of the VW Type 1 on the 4CV’s design, there is little doubt that the Dauphine was benchmarked directly against its German competitor. This led to the engine, carried over from the 4CV, being increased in capacity to 845cc to improve the car’s performance.

Image: pubanciennes.canalblog

The car was officially launched at the Geneva Motor Show in March 1956. Although pre-launch press publicity had referred to it simply as the 5CV, it was given the name Dauphine in reference to its position as heir apparent to the (4CV’s) throne. The new model was 275mm (11”) longer than the 4CV and had a conventional ponton-style three-volume profile, albeit rounded off in a nod to aerodynamics. The monocoque design weighed 650kg (1,430lbs) an increase of just 30kg (66lbs) over its predecessor.

One unusual feature was a separate compartment for the spare wheel underneath the front boot, which was accessed via an external lid below the raised centre section of the front bumper. Another neat touch was the scallops in the rear doors that accommodated the engine air intake grilles ahead of the rear wheel arches. The scallops were in turn accommodated by sliding, rather than winding, windows in the rear doors.

The standard transmission was a three-speed manual gearbox carried over from the 4CV, although a push-button operated three-speed automatic(3) was offered as an option. The latter was thought to improve the Dauphine’s appeal to female drivers, as was a range of pastel colour choices. Later, a four-speed manual transmission was offered on the short-lived 1961 Ondine luxury version, and also on the more successful Gordini sporting variant, which had an engine tuned to produce 37bhp and was fitted with disc brakes all round from 1964.

There was a sting in the Dauphine’s tail; a function of its rear-engined layout, which placed 60% of the car’s weight over the rear wheels, coupled with rudimentary swing-axle rear suspension. This could cause an abrupt transition to oversteer when cornering at speed. Renault attempted to tame this tendency by fitting a front anti-roll bar and specifying low front tyre pressures, but it remained an issue, and a trap for the reckless or unwary.

The Dauphine’s other major weakness was corrosion. Its lightweight construction and inadequate rustproofing made it no match for some of the harsher climates to which it was exported. Early success in the US, where over 100,000 examples were sold in 1959, was quickly undermined by a reputation for extreme fragility. In this regard it compared unfavourably with the crude but tough VW Beetle, which retained its crown as leading US import.

1958 Renault Caravelle

The Dauphine was only produced in a single body style, but there were pretty convertible and coupé models  built on the same platform and mechanical package called the Caravelle (or Floride until 1962 in markets other than the UK and USA). The Caravelle was designed by Pietro Frua at Ghia. It was launched in 1958 and sold for a decade. The Dauphine itself remained in production until 1967 and, like its predecessor, was exported widely. A total of 2,150,738 cars were sold over eleven years before it was replaced by the Renault 8.

(1) The VW Type 1 was itself a copy of the mechanical layout employed by the Czechoslovakian company Tatra since it produced the V570 prototype in 1931. Tatra actually launched legal action against VW for copyright infringement, but this was brought to an abrupt end by Germany’s invasion of Czechoslovakia in 1939. VW finally paid a modest DM 1m to Tatra in an out-of-court settlement in 1965.

(2) In layman’s terms, the problem is that the weight of the engine acts as a ‘pendulum’ at the rear end. If the driver enters a bend too fast, then lifts off, the rear tyres can lose grip, causing the rear end to break away, a phenomenon known as lift-off oversteer. In extremis, the car can leave the road backwards, with dangerous consequences.

(3) In reality, it was just an electromagnetically operated clutch, not a fully automatic transmission, but was similar to the system VW offered on the Beetle.

Author: Daniel O'Callaghan

Shut-line obsessive...Hates rudeness, loves biscuits.

28 thoughts on “One Last Push (Part One)”

    1. Yes, probably best left alone, although that’s a very attractive show car. All the nicest details would have had to rationalised out for production. The combination of wicker door cards and visible welding seams is fun but not very practical (imagine trying to clean the door trim!)

    2. The “Fiftie” would have been the only Renault I would have bought immediately (the “Wind” almost got shortlisted, but the interior spoiled it). Different people, different taste.

      I like the Wheels of the 4CV, how they are bolted on the drum brake (like on Panhards). Pretty cool.

  1. Thank you, Charles. Yes, the steel wheels on the 4CV look like they have been widened, as was the fashion back in the 70’s if I recall correctly, putting extra strain on hub bearings, sometimes with disastrous results.

    There seems to be a ring of bolts around the perimeter, just inside the rim. Were they in two parts, I wonder?

    The 4CV is an endearingly pretty car, I think. It has something of the character of the 1957 Nuova 500.

    1. It is pretty – there’s some almost Art Deco detailing on some versions – on things like grilles.

    2. Those wheels actually are made from two parts that can be separated by loosening those bolts.
      The spare wheel originally only was the outer ring with a tyre and the inner part stayed on the hub.

    3. Hello Dave,

      That rings a bell, now you mention it. Didn’t Beetles have a similar arrangement, early on – wheels with no centre?

    4. Hi Charles. Yes the pre-1967 Beetles had a similar, if less extreme design:

      Fortunately, they were secured with nuts rather than studs, so you had the studs fixed in the brake drum on which to locate the wheel when replacing it.

  2. Got to admire Renault’s pragmatic approach with its rear-engined models by having its saloons feature only 4-doors to widen its appeal, whereas other small rear-engined saloon rivals with the exception of the Renault-derived Hino Contessa, Skoda 1000 MB (plus later models), Simca 1000 and SEAT 850 (plus 600-based SEAT 800 4-door) as well as a few Japanese Kei / Small Cars (like the Mazda Carol plus Carol 600) largely only featured 2-door saloons. Arguably to their detriment.

    At the same time prior to the more advanced Renault R4 (and R3), could Renault have developed its own small entry-level Fiat 600-type model below both the 4CV and Dauphine powered by the 603-747cc Billancourt motor? Did Renault explore such an avenue derived from either the 4CV, Dauphine or R8 prior to opting for the FWD R4?

    On the subject of rear-engined cars in general, could its drawbacks have been largely remedied with the right combination of suspension layout* and lightweight all-alloy engines to give near 50/50 weight distribution?

    Some have argued 50/50 weight distribution is not necessarily better for rear-engined cars, at the same time only the Renault R8 at least in Gordini (if not regular spec) spec appears to offer slightly better weight distribution at 46/54, whereas surprisingly the Imp’s figure was 42/58 despite the engine’s weight being 176 lbs / 80kg, while the Simca 1000 as well as the Skoda 120 were claimed to be 35/65 and 38/62 respectively (the more recent Renault Twingo / Smart ForFour possessing a 45/55 weight distribution).

    *- Depends of course on what suspension layout would be ideal for small rear-engined cars (prior to the Porsche 993 sportcar’s alloy multi-link rear suspension system) and which rear-engined cars came the closest to achieving the ideal in terms of suspension.

    1. Hello Bob,

      The Volkswagen ID.3 has rear wheel drive and 50 / 50 weight distribution. Its electric motor is at the rear, but given the weight distribution, I guess it might as well be front engined and rear wheel drive, like a Mazda MX5 or similar, or even a mid-engined car.

    2. Charles

      Will have to admit that have not really been keeping track on EVs in general (more partial to less disruptive drop-in fueled solutions though that is another matter).

      Somewhat surprised no carmaker has achieved a similar 50/50 weight distribution with rear-engined ICE cars whether historically or up to recent times given the trend towards compact downsized engines.

  3. The old side valve Ford Anglia and Prefect had wheels like the Beetle. The Renault wheels differ in having a detachable rim , and I do wonder if that lovely blue/green example pictured has had the rims reversed to make it look more up-to-date.
    The Renault Dauphine was the first car I ever saw advertised on UK TV, and I still remember the jingle – it must have done wonders for Renault sales.

  4. I always thought the Dauphine was very pretty if nothing else, only realised later that the styling was largely copied from the RWD Fregate model.

    1. Hi Mervyn. The Dauphine was a pretty and nicely detailed car. I particularly like the rear door treatment and those little ‘ears’ on the C-pillar containing the lights.

      Not that I remember it, but the Dauphine holds a special significance for me. It was the first car I ever travelled in, on the journey home from the maternity hospital where I was born. My late dad had a BMW Isetta bubble car but, with me on the way, it wouldn’t have been big enough to carry a second child, so was replaced by a grey Dauphine.

      Here’s a nice example of the relatively rare Ondine ‘luxury’ version:

  5. Automobiles are quite tolerant of weight distribution. Placing the engine behind the rear axle line does not necessarily lead to the behaviours popularly associated with the arrangement. In the case of the Renault 4CV, VW Beetle, etc. the cause of the “oversteer” was excessively high rear roll centre allied to excessive camber change with suspension travel. It didn’t help that in many of these cars the roll axis was also too steeply inclined.

    What Porsche did to correct its handling problem is exactly what Renault did (and what Chevrolet did). Renault corrected the geometry of the suspension on the rear engine Alpines, discarding swing axles for double wishbones in the later iterations of the car. Porsche corrected the geometry of its suspension, migrating from swing axles (356) to semi-trailing arms (911) and finally arriving at a multi-link rear suspension. For both manufacturers the goal was to get better camber control (by dramatically lengthening virtual swing-arm length) and reduce jacking forces (by lowering roll centre height). Both makers altered roll moment distribution and amended roll axis inclination.

    What you may wish to do is drive an older Mercedes with their take on swing-axle rear suspension. The engine is in the front in this case. Try you luck hard enough and you may learn a frightening lesson. The low pivot swing axle cars Mercedes manufactured do offer improvement over the conventional swing axle. They tend to be more tolerant, but you can still encounter the lesson. And the engine remains resolutely in the front of the car all the while.

    The infamous “oversteer” attributed to rear engined cars is not to do with where the engine is located or where the centre of mass is located. It is about what the suspension design is.

    1. Hi J T. You’re right, as I understand it, that the problem of snap oversteer was often more to do with the rear suspension design than weight distribution per se. Didn’t the front-engined RWD Triumph Herald and Spitfire suffer from an unloaded rear wheel assuming an extreme positive camber angle and ‘tucking under’ when cornering hard? This was caused by the primitive swing-axle rear suspension Here’s a rather terrifying image of this in action:

      I’m no suspension expert, but that looks seriously wrong!

  6. thanks J T for your clear exposition of swing-axle dynamics.
    my first two cars, back in the 60s, were a Fiat 500 and a ’57
    Beetle. I drove them with all the vigour of unskilled youth
    but never came to grief. in relative maturity however, my
    beloved 205 Gti had plenty to show me about lift-off oversteer.
    I did quite some miles in a Dauphine, a sweeter car than the
    500 or VW. in the 60s the 4CV’s detachable rims were just the
    thing to fit to home-made alloy centres for special builders
    cobbling up formula 750 (Austin 7) racers.

    1. Driving “with all the vigour of unskilled youth” is so apt – and will chime with many of us. But Daniel’s Herald illustration is a classic example of period testers pushing things to limits in the wide open spaces or airfields and the like. On real roads where in my youth I indulged my inner hooligan in Heralds & Spitfires, despite more than one ‘phenomenal avoidance’ I never succeeded in emulating that image.
      In the pre-global warming days, rear-engined vehicles came into their own every winter as our north-of-the-Trent roads disappeared under a blanket of snow from January to Easter. Hence the relative popularity of the VW Beetle, Fiats 500 & 600 and Renault 750 – which is how the Acton-built 4CV was known in GB.

  7. There is a pristine condition Renault Dauphine garaged quite near my home and I sometimes encounter it when walking around. I was unfamiliar with the model and curious about it, so this is a very helpful article. Thanks!

    1. Good morning Chris and thank you for your kind words. Here’s a photo of the abovementioned spare wheel compartment, one of the Dauphine’s more unusual features:

      Much more practical than a well in the boot floor as there’s no need to unpack the boot to get at it.

    2. Does anyone else find the image above pareidoliac, or is it just me?

    3. You’re on the gin too early Daniel, it’s only midday! Although now you mention it…..

    4. It’s always after midday somewhere, Adrian. Cheers!

  8. Looking at that pic of the Dauphine with its’ tongue out, I noticed the little levers under the headlights – I believe these were for altering which way the lights dipped.

    1. Hi Mervyn. The Renault 4 also had those little levers under the headlamps:

    2. …and the Renault 12 had them too. They are headlamp beam adjusters, for when the car is laden. No little dials on the dashboard in the 1970s, but a useful feature on softly sprung French cars. The headlamps on the 12 could also have their reflectors adjusted for the convenience of intrepid continental explorers, which was quite clever. This was done from the back of the lamp unit.

  9. Here’s a film about the Dauphine’s design and testing. It’s interesting, although it follows the now traditional narrative of research / design concept / testing / production.

    More films are listed further down the page, including one about its aerodynamics.

    I find Car Design Archives a fascinating site – I could (do) spend hours going down its rabbit holes.

    1. Nice video, and a good complement to the piece. Thanks for sharing, Charles.

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