Monday, April 27, 2009
Triumph Vitesse
In 1968, concerned by the progressing rust on my Austin-Healey Sprite, I bought a 1964 Triumph Vitesse Convertible.
Not one of my better decisions.
The Triumph Herald & Vitesse range of cars, introduced in 1959, probably holds some kind of record for the number of highly publicised new features which turned out to be evolutionary dead ends.
To be fair, you have to put them into a 1959 context when British small cars (Standard 8, Austin A35, Morris Minor) were blobby affairs with little visual, technological, or behavioural appeal, just offering minimal mobility for grateful post-war families.
Against that background, the Herald, with its low build, huge glass area, frameless windows, tail fins, all-independent suspension, rack & pinion steering, remote gear shift lever, all-opening bonnet/wings etc, seemed like a space-ship.
Certainly the driver visibility set an excellent benchmark which has rarely been approached since & is unfortunately not likely to be again.
The driving position & steering were good too.
And the boot space & shape & accessibility.
But the much-vaunted independent rear suspension turned out to be by swing-axles, which had been a bad-enough idea on VWs & Renault Dauphines, but were worse on a front engined car with much more variation in rear axle loading.
Every vertical movement of the suspension is accompanied by lateral movement of the road/tyre contact patch, so the car squirms over bumps.
Every change in suspension height, due to load or bumps or cornering, results in a change in camber angle of the tyre & hence cornering force, so handling is variable & unpredictable.
In extreme cornering conditions, the system becomes unstable & can lead to catastrophic loss of adhesion at the rear, as Ralph Nader publicised in "Unsafe at Any Speed" about the Chevrolet Corvair.
Also vaunted was the separate chassis (going against the post-war trend) with bolt-on body panels.
That did allow flexibility in easy introduction of multiple models (Saloon, Coupé, Estate, Convertible) & allowed the fully-opening bonnet/wings assembly, which were good points.
It soon became obvious, however that the panels were bolt-on, rust-off.
Even sooner, it was obvious that the flexibility extended to lack of rigidity of the body/chassis assembly, resulting in creaking & rattling & a general feeling of flimsiness.
Frameless side windows are a great luxury feature on great luxury cars, but can easily lead to water leaks, wind noise & stiff window winding if done less than perfectly.
Say no more.
The number of grease nipples needing frequent attention was greatly reduced.
Partly by using unlubricated plastic bushings, which rapidly wore out & needed replacing.
Partly by an odd arrangement on the steering pivots, where you were supposed to unscrew little plugs, screw in oil nipples, squirt in oil, remove the oil nipples & refit the little plugs.
Hard to think that was a smart move either.
An ingenious fuel reserve system was provided in the fuel tank placed vertically in one side of the boot.
The fuel outlet was via a J-shaped pipe rising at 45° to the top of the tank & equipped with a handle.
Turning the handle turned the end of the J either up (normal) or down (reserve – nearly another gallon).
Actually very simple & useful, but don't mention safety.
The steering column incorporated a telescopic section which was supposed to provide some protection in a collision & could also be used as an adjustment for the steering wheel position, but only with a spanner or preferably a torque wrench.
The dashboard was in a sort of matt-grey papier maché which was supposed to offer some impact protection.
The famously tight turning circle "better than a London Taxi" really deserved to be copied, but wasn't.
The Convertible model added, of course, the open-air option you love or hate (I love).
And kept most of the 4-seater capacity & boot space.
But seriously reduced the visibility to side & rear, especially as soon as the plastic windows lost their initial transparency.
And it reduced the structural rigidity even more.
What surprised me the most was how much more draughty it is in a 4-seater convertible than in a cosy open 2-seater with high sides & back panel.
Heralds had a 948cc 4-cylinder engine, later increased to 1147cc & 1296cc.
The Vitesse variant introduced a 1596cc straight 6-cylinder engine, probably one of the smallest ever.
That means much lower than optimal-sized cylinders, with resulting poor efficiency, compounded by more internal friction.
Compounded by the fact that this was (I think) a downsized version of a 2000cc engine, so was very heavy & bulky.
Performance was better than the Herald, but not so much as all that.
And handling was very nose-heavy.
Most L6 engines (think of BMW) at least manage to be beautifully smooth & a 1600cc one should have been smoother, but for some reason this one managed to be rough at high speeds, maybe due to crankshaft flexibility?
Later versions had a 2000cc engine, which was considerably quicker.
Gearboxes were universally 4-speed in those days (with no synchromesh on first gear) but many Vitesses, including mine, had a Laycock Overdrive unit, working on 2nd, 3rd & 4th gears, giving 7 gears in all.
This was the automotive equivalent of bicycle derailleur gears.
The normal 4 gears were operated by gear lever, clutch pedal & throttle pedal, as usual.
The Overdrive was operated by an electrical switch, which actuated a solenoid which allowed an oil pump to move a double-sided cone clutch, which engaged an epicyclic overdrive ratio, like changing the front chainwheel on your bike.
When things went right, this resulted in a smooth shift like a good automatic gearbox.
Often though, there would be a variable delay & some kind of thump or shudder.
Endless variations of throttle-pedal & clutch-pedal actuation had more or less good or bad effects on the process, depending on speed, slope, temperature etc.
Juggling with the gearbox & overdrive ratios was too much like 27-speed bikes.
My Overdrive never needed attention, but the addition of a lot of mechanical, hydraulic & electrical parts was unlikely to be good for reliability and the pumps, gears & clutches were bound to spoil efficiency.
The 5-speed gearbox was going to be a much better solution, one day.
I didn't have any problems with my Vitesse Convertible, but never liked it much either.
I did replace the transverse rear spring with a lowered one, which improved the handling & stability a bit.
The final versions ditched the swing axles for a proper multi-link system which presumably worked much better but presumably cost more than could have been afforded for the Herald.
I sold mine after less than a year, with no regrets.
Parting thot: "Imitation is the sincerest of flattery." - Charles Caleb Colton
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