What is he on about this time you may well ask? Rear ends my friends are one of my favourite parts…
Location of same is one of the most critical bits of their effectiveness. When I spotted this cutaway of a 1958 Grand Prix Vanwall, I thought what a wonderful pot-pourri of all of the bibs and bobs which makes a front-engined cars rear end provide grip, stability and control as le pilot applies the motive forces via the throttle to the road.
One of my current obsessions is the brilliant work of ‘cutaway artists’ like Vic Berris, Theo Page, Paolo D’Alessio, Claude La Tourette, Brian Hatton, Bill Bennett, Tony Matthews, Bruno Betti, Giuseppe Cavara, Yosihiro Inomoto and others. I post their work regularly on my primotipo Facebook page, which is always well received. An ‘eyeful is better than an earful’ in terms of understanding what makes something tick. My simple little brain cannot conceive just how they conceptualise their work let alone create it.
So, to my reaction- ‘Wow, that IS a textbook illustration of the way to locate, brilliantly, a live rear axle. Or in this case, a de Dion axle. Vanwall’s Colin Chapman chassis design was the state of the art in that immediate pre mid-engine era, whilst noting Cooper’s first F1 championship victory was also in 1958. That was Moss’ win aboard a T43 in Argentina. Vanwall won the Manufacturers Championship that year whilst Mike Hawthorn took the drivers title aboard a Ferrari Dino 246, in 1958 trim the Italian car also utilised a de Dion rear end.
Chapman’s spaceframe designs, the art he was honing on his Lotus sportscars was first applied to a single-seater for someone else- Tony Vandervell.
The de Dion axle is clear in the cutaway, as are the inboard disc brakes. The de Dion tubes upwards and downwards movement is controlled by a Watts Linkage, the springing medium is a coil spring/damper or Chapman Strut. Lateral movement is controlled by a Panhard Rod. Fore and aft movement of the de Dion tube is controlled by two Radius Rods extending forward of the de Dion tube to the cars chassis on each side of the racer.
The engineering of these cars was first class, the execution of tool-room quality, check out the article I wrote on Vanwall a while back which explores the cars in more detail by following the link at the articles end.
Art Credit…
The irony, in naming all of the talented cutaway dudes above is that the drawing, published on ‘The Nostalgia Forum’ is not credited! If any reader knows the artist please advise me and I will update the caption accordingly. The chap is a skilful one whoever he is.
Vanwall chassis ‘VW4’, as per the fuel tank tag- said aluminium tank beautifully fabricated and simply located to the spaceframe chassis by rubber bungee straps. de Dion axle, inboard discs and Chapman Strut- it looks like a simple co-axial coil spring/damper unit to me! Two forward facing radius rods also clear at lower right (Ludvigsen)
Nomenclature…
James Watt patented his mechanical linkage in 1784 when it was described in the patent specifications of his steam engine. The Panhard Rod was invented by the French automobile manufacturer at the dawn of the twentieth century. Whilst named after Jules-Albert de Dion, the co-founder of De Dion-Bouton, ‘the tube’ was invented by one of his partners, Charles Trepardoux for use on the company’s steam tricycles. ‘Chunky’ Chapman’s strut was first used on his 1957 Lotus 12 Climax F2 and later F1 car but the design’s origin rests in the near vertical coil spring struts on William Stout’s 1932 Stout Scarab. Alexander Graham Bell developed spaceframes based on tetrahedral geometry (triangular pyramid) for nautical and aeronautical engineering purposes between 1898 and 1908. There aint nothin’ new under the sun my friends, rarely anyway…
Superb detail of fabrication and finish down to ‘Vanwall’ spinner cap. Disc brakes are Goodyear designs made by Vanwall. Otherwise description as above (Ludvigsen)
1958 Belgian GP, Spa, 15 June…
The photos in support of the drawing were taken in the Spa pits by historian/author Karl Ludvigsen.
Clearly, one of the chassis photographed is ‘VW4, raced by Stuart Lewis-Evans that weekend and famous in the pantheon of Vanwalls as the first British car to win a championship grand prix- the ’57 British at Aintree in the hands of both Brooks and Moss. Sadly, this car was destroyed in the October 1958 Casablanca, Moroccan GP accident which befell Stuart Lewis-Evans and from which he later died.
The photos are probably all of ‘VW4’ as it was clearly unclothed at the time. ‘VW5’ was raced by Brooks and ‘VW10’ by Moss that weekend. Interestingly the Vanwall numbered #48 in the background of the front of the car shot (at the end of the article) is not listed in the race results- perhaps the car is a spare or had not yet had its Spa race number applied. Race numbers for the weekend were Brooks #4, Moss #2 and Lewis-Evans #6..
It was a great race for the Acton team with Tony Brooks winning from Q5, Stuart Lewis Evans was 3rd from slot 11 with team leader Moss out on lap 1 after muffing the fourth to fifth shift exiting Stavelot and popping the engine. A mitigating factor was the interminable time spent on the grid which boiled engines and drivers nerves- pole-sitter Mike Hawthorn’s Ferrari Dino 246 was bubbling before the flag was dropped but survived to the end of the race, but only just, as a piston failed heading down the hill to the finish line on the last lap, in 2nd place.
In an amazing finish Brooks gearbox was tightening, some way towards failure, Hawthorn had an engine pop just before the line and Lewis-Evans finished with a broken right front upper wishbone. The first healthy car to complete the distance was the ‘Chapman Strutted’ Lotus 12 of Cliff Allison in 4th place, the little cars Coventry Climax FPF four cylinder engine giving away some capacity to most of the opposition, racing as it was at 2.2 litres. It was a mighty fine performance by Allison and the tiny little Lotus on a supreme power circuit, the ultimate test of high speed precision and testicular size!
This shot shows the attachment of the de Dion axle to the upright or hub, parallel radius rods also clear. Favoured wheel combinations in 1958 were old fashioned wires at the front for greater driver feel and magnesium wheels at rear (Ludvigsen)
In fact the Vanwalls had the speed for most of the weekend in a close contest for pole, Moss was so confident of his time not being bettered that he/the team made the decision to sit out the last session only to have the Ferrari’s of Hawthorn and Musso better his times. In a sign of a different era, Denis Jenkinson in his MotorSport report of the race notes that ‘Having nothing to drive (as his Vanwall was in bits for final race preparation) Maserati lent Moss a new experimental sportscar they had with them, this being a V12 cylinder 3 litre engine in a modified 300S chassis’, imagine that happening today! Still, Stirling was a Maser racer throughout his career.
Bibliography…
The GP Encyclopaedia, MotorSport July 1958
Photo Credits…
Karl Ludvigsen, The Revs Institute
Tailpiece: It seems a lost opportunity not to show the gubbins at the Vanwall’s front in addition to the back, Spa ’58…
Water radiator and behind it the engine oil dry sump, engine itself mounted well behind the front axle line. Aluminium alloy head and Rolls Royce ally block, in 1958 form the Bosch injected, DOHC, 2 valve, 4 cylinder 2.5 litre engine developed circa 280bhp on pump fuel- down from circa 290bhp on alcohol. Wire/Alloy wheels referred to in shot above shown on the two cars in shot (Ludvigsen)
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