The Comet

It is understandable that, after a considerable period of time, even cars that had a reasonable production-run should be forgotten by the majority of those associated with the motoring world. But there are several which were either made in very small numbers indeed or which never went into production — the sad “lost causes”, or “never-successfuls” of the automotive firmament. Such a car was the Comet, promising as it seemed when it was announced early in 1935.

It was to have been a fast small-car of advanced specification, to be manufactured by the Invicta Welding and Engineering Company Ltd at the lnvicta Works, in Sutton, Surrey. It was the brainchild of a Mr Kirkland, who, when designing the Comet, said he was as much concerned with comfort and refinement, and of course reliability and durability, as with speed. The engine, of I 203cc, was in the 10hp taxation bracket. It had a bore and stroke of 63.5 x 95mm and would have commanded an annual tax of just £7.10/(0.50) in 1935.

It is an established fact that producers of motor cars in small numbers have seldom been able to bear the expense and manufacturing complication of making their own engines. So it is interesting to try to define what proprietary power-unit Mr Kirkland had adopted for his ideal car. We know the bore and stroke, assuming he had not bored out or lined-down the cylinders, or had made a new crankshaft. However, this takes us nowhere. When Vale Engineering was using Triumph engines, HRG Meadows (and later Singer) power-units, Buckler and others were relying on Ford-power and AFN put various makes of bought-out engines into the Frazer Nash, what did Kirkland do?

He could have been using a bored-out BSA engine, except that this was a side-valve power unit with a two-bearing crankshaft, whereas the Comet had vertical overhead valves and conventional push-rod-and-rocker valve-gear and three-bearing crankshaft. The Ford Ten comes close and could have been given overhead valves but if you read on, you will see the improbabilities of this. I liked the thought of a Talbot Ten motor, but dismissed it for the just-explained reason, and if a (bored-out) Riley engine had been available, which I think unlikely, would Kirkland have foresaken its excellent hemispherical cylinder head? No, I think we must assume, like the ambitious Geoffrey Taylor at Alta, that the Invicta Works was equipped to make engines, although more than skilled welding is involved.

In fact, the Comet had a truly advanced power-plant. The cylinder block was of nickelcast iron, with chrome liners, the three-bearing crankshaft of chrome nickel. Y-alloy was used for the crankcase, and the pistons were of heat-treated silicon alloy, with duralumin conrods. Nor was that all. The cylinder head was of hiduminium, with manganese-bronze valveseats and bronze valve guides. The valve-gear, although conventional, embodied duralumin rockers and push-rods, the latter steel helmeted. It was claimed that the combustion chambers gave good gas turbulance round the sparking-plugs, which were fired from a special kind of coil. The two inlet manifolds each had a downdraught carburettor, hot-spotted from the three-branch exhaust manifold at two points.

Carburettors and manifolding were on the off-side, as was the long water off-take pipe. The valve cover, and a domed tappet cover on the near-side of the Comet’s engine, were retained, respectively, by three, and two, big threaded discs, which should have given me a clue to the engine’s origins, if it was bought out, but didn’t. The water delivery pipe from the tall radiator fed into the front of the head, for the pump cooling system. Lubrication was by a submerged oil pump which fed, via a filter, a galley cast in the cylinder block, from which oil went to the main bearings and from another channel to the valve-rocker shaft. Oil then drained back to the sump via the push-rod tunnels, there being a complete absence of oil pipes of any kind. The sheet metal sump held 1.5 gallons of lubricant and possessed air tunnels for cooling purposes, Riley fashion.

The drive went through a Borg & Beck clutch to a four-speed unit gearbox giving ratios of 18.5, 10.8, 6.4 and 4.5 to 1, with a 24 to1I reverse. This power pack was four-point mounted, on Hartford Silentblocs at the front, rubber buffers at the back. An MG-like remote-control tunnel covered the rods uniting stubby central gear lever with the gearbox. Further advanced thinking was seen in the Comet’s chassis frame. There was a massive, drilled, X-shaped central cross-member, and independent front suspension was used, at a time when, although this was to be found on continental cars such as Delage, Mercedes-Benz, Peugeot, etc and featured on some American cars, only Alvis used it in Britain and Vauxhall had yet to impress visitors to the 1935 Olympia Show by introducing it, enabled to do so by borrowing the Dubonnet system from Opel, which was also part of the General Motors’ empire.

It was then unknown on small cars. Yet here it was, in the Comet’s specification. I think a proprietory design may have been incorporated. It used transverse coil springs, coupled to the lower of two fabricated wishbones by bell-cranks. Two friction shock-absorbers were fitted on each side and the front wheels remained vertical as they rose and fell. Accurate Bishop steering gear, half-elliptic rear springs with two large hydraulic shock-absorbers, Silentbloc chassis bushes to reduce maintenance chores, an 8-gallon rear fuel tank with mechanical feed, and centre-lock wire wheels completed the Comet’s specification. It had a wheelbase of 7ft 9in, a front track of 3ft 10in and a rear track of 3ft 9in. The plan had been to offer it in three forms, two-seater, four-seater (both at £435) and saloon, the last, perhaps all three bodies, to be contracted out to E D Abbot Ltd of Farnham, which in 1935 was making special bodies on Lagonda Rapier chassis and who were also responsible for racing bodywork, such as that on Le Strange Metcalfe’s Abbot-Nash.

Since the beginning of 1935 an experimental Comet had been on test. But as the announcement in January 1935 stated that “it is expected that a speed over 80mph will be possible”, presumably the engine in that test chassis was not fully developed. By the release date it was claimed that nearly 50bhp was being developed at 5000rpm, with a safe rev-limit of 5500rpm, which was exceptionally high for a production car at that time. At 3000rpm the Comet’s engine gave 30bhp. Later in 1935 production was said to be commencing. But did it ever commence?

This promising little car faded away, like heavenly Comets do. Does anyone know why? WB