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At risk of diverting this thread into a full-size discussion: the problem with the swing axles on the Herald, Spitfire, early GT6 and (dare I say) early Porsches, as well as pre-WW2 Auto Unions, was that the axle itself formed one link of the independent rear suspension, so that the wheel was constrained to move through an arc as it moved up and down. This gave negative camber (good for stability) on downward movement, but positive camber (unstable) on upward movement. Hence the dramatic runaway positive camber photos shown earlier in this thread. If the suspension is more complex (eg semi-trailing link or twin wishbones), the wheel moves in a more-or-less parallel path, but the length of the driveshaft changes, so some sort of sliding spline or compliant rubber doughnut is needed, or two CV joints. Universal joints like they use on rear-drive propshafts are unsatisfactory anyway, because the speed of rotation varies depending on how much the driveshaft is deflected, which puts loads back into the transmission. That's why CV (constant velocity) joints are preferred.
In my experience, the only problem with swing-axle suspension is talentless journoes with whom I wouldn't trust with a supermarket trolley. They have trotted out the same old tommyrot for the best part of 80 years, and still do. Bless 'em.

Mercs with swing-axles included the 300SL coupe that won Le Mans, 1952, and the GP cars of the mid 1950s, and the 300SL road cars, Beetles, 356 Porsches et al. There's just a chance that Rudi Uhlenhaut and Ferdinand Porsche knew a little more about engineering than the angry twits who constantly drivelled on in comics in the hope of making a name for themselves.

Vic Elford started his rallying career with a Triumph Herald. "Great little car," he said, puffing on yet another cigarette...

Down many years it has been my fortune and misfortune to share cars on press launches; this is how it is: sent off in pairs to evaluate a new car. I wonder I am still alive.

Yes, swing axles will travel the length of their arc, but the speed at which this occurs during hard cornering is always extremely high. And when it 'flicks' you bang on opposite lock, and all is well. It's fun. Those who can't do it freeze, and then criticise the engineering, whereas the real fault lies with a total lack of talent - the beige-socks brigade!

Early (1969) 917s? Wandered. Yep. At speeds never previously attained. Vic Elford loved every 917 he ever saw and drove which is just one reason for people at Zuffenhausen today continuing to hail him as the best driver the company ever employed.

No, of course, the 917 didn't have swing-axle suspension, but this didn't stop David Piper saying: "You know, when we tried the 917, you know, it jumped all over the place, you know, and at speed, you know, it, ha-ha, behaved like a Vokeswagen (sic), you know, with, you know, positive camber, you know, at the rear, you know."

Have a look at Piper's lap times for Spa, 1970, please. And then compare them with those of Siffert and Rodriguez.

I stopped listening years ago. One grows old and very, very tired...
So only talented racing drivers can control a Triumph Herald ,whilst joe public ,beige sock brigade , will have troubles with it Strange as the car was meant for the average driver and youngsters with not a lot of experience .

Steve
Hi, Trisha.

This seems like the typical discussion between a theorist and a practical man! I have my beige socks on today, by the way, Steve 😀.
We could debate this forever, but, from an engineering standpoint, the severe camber changes which come with swing axles reduce the levels of rear-tyre grip. Quite apart from debates over whether this is 'safe', reduced grip is seldom a good thing, which is why more recent designs have gone to twin wishbones or multi-link designs, with an aim, among others, of keeping the tyres perpendicular to the road.

The pre-WW2 racing designers who used swing axles did so because reliable CV joints were not available then and a beam axle or De Dion setup is not practical if the engine is mounted very close to the axle. I'm not sure what was Mercedes' rationale, but I would guess that they thought the benefits of reduced unsprung weight outweighed the handling disadvantages.

I recommend Reinhard Seiffert's excellent book An Miracle on 4 Wheels' for a deep examination of this whole subject.

Comments eagerly awaited!
Mike
 

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Gordon Steadman
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My only contribution relates to the difference between the GT6 and the Alfa 1300 GT Junior. In the GT6, sideways action was a matter of the car deciding - and yes I was up to catching it!

In the Alfa, it was because I decided and the car just did exactly what it was told. The back end of that Triumph was not something that inspired confidence.
 

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I did play around on making a 4wd slot car chassis with swinging axles front and rear. Never went any further then this stage with the idea.

 

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Caused a bit of a stir when current..
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Eddie
That Second Gen Corvair was a good one! The post '65 Corvairs, like the one in your pic, had semi-trailing arm rear suspension which handled a LOT better than the first version, which did have swing axles and would oversteer in the garage with the engine switched off!
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A '62 Corvair 4 door was my first car, bought from a USAF Sergeant who was returning home, and I had it for a couple of years, but I couldn't afford the fan belts, which kept flying off. The later 'upgrade' to a 'Super Turbo Air ' engine didn't help matters, it had al of 95 horsepower, and getting all that lot down to the ground was pretty difficult via its swing axle rear end. I was going to get a camber compensator spring, like the ones fitted after market to Spitfires and Mk 1 GT6s, but I ran out of money on fan belts...……...

This is First Gen Corvair below.
 

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Jim Moyes
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Those "talentless journoes" obviously held some influence over the bigwigs at BL because they went back to the Herald's predecessor, the Standard 10 for the rear axle of it's successors the Dolomite, TR7 and even the Marina.
 

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Jim Moyes
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Yes, you're probably right, Leo!

I wonder if they actually noticed much change when they chopped their Heralds in for the 1300, then the Toledo, then the Acclaim, and then ,depending on whether they had been POWs of the Japanese, the Rover 213 or Civic.
 
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*** Leo A Capaldi ***
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My sister had a convertible Herald, it never let her down nor did her any harm. On the contrary my Sunbeam Imps encouraged fast driving and got bounced off things "occasionally". No need to mention reliability differences!
 

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Gordon Steadman
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My sister had a convertible Herald, it never let her down nor did her any harm. On the contrary my Sunbeam Imps encouraged fast driving and got bounced off things "occasionally". No need to mention reliability differences!
Absolutely, Liz (my sister) had no trouble at all with hers - apart from steep hills! - she always drove fairly sedately so never got into the 'zone'. With a 2 litre 6 up front, things were somewhat different.
 

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There's a woman who lives in the Forest of Dean near me who has one of each version of the Herald.

An ordinary saloon, a coupe, a convertible and an estate. Oh yes, and a 13/60 for Sundays! She drives the Estate as her every day car and I see it most weeks, or did until I decamped to Northants for the duration of the crisis.
 

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Jim Moyes
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Wot!?
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No Courier van?
 

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Please forgive me if I have posted this anecdote before!

Regarding the straight line stability of the swing axle arrangement I well remember my father telling me of his experience at the 1937 Donington GP. He went with my grandfather and both were regular attendees at the circuit. They arrived during practice and walked up from the car park to a point on the main straight where a high stone wall crossed the track ( ! you won't see that feature on a modern circuit). As they reached the track, an Auto Union blasted by at full chat "swerving all over the road". Grandfather let out the involuntary exclamation - ooya b*gg*r ! Neither of them had seen anything faster than an ERA before and this car was probably 40 mph faster than those and at the limit of control over the bumps.

Grandfather had been on the front lines in WW1 and was not easily shocked, and this was the only time my father heard him swear.

Keith
 

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An Auto-Union driven by Bernd Rosemeyer won Donington 1937. "Probably 40mph faster".

Self-delusion has long been a trait of mediocrity...
 

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Absolutely, Liz (my sister) had no trouble at all with hers - apart from steep hills! - she always drove fairly sedately so never got into the 'zone'. With a 2 litre 6 up front, things were somewhat different.
I had a tweaked 1600 Vitesse with a SAH rear anti-roll/sway/camber compensator bar. Worked for me.
 
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