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'Sidetracked' additions:

Chapter 4 – Committed

Pages 33, 35, 36a, 36b, 42

Page 33, beginning

    Our small manufacturing company, like so many at the height of the eighties boom, was looking for additional ventures in which to invest over-healthy profits. That said, even in the excessively heady late 1980s, any speculative proposal without proper planning was taken as a request to finance an excursion into the unknown. It had to be feasibility first then finance follows.
    In this instance, we had a long list of checks, both visual and mechanical, before launching into the realms of specialist motor manufacturing. First off was the practicability of fitting a thirties-style aluminium body to a stripped-down altered late-1970s Cadillac using a monocoque cab-&-trunk combined with a forward half-chassis.  
    To check this out, we contacted several coachbuilders and specialist panel beaters.
    Having explained in as much detail as feasible by telephone, we did eventually obtain more than one assurance that our intended idea was in fact possible. The cost, although high, was not prohibitive. However, knowing that some serious face-to-face meetings would be needed to cover the necessary detail, we made notes for later use.

 

Page 35, para 4 

    We checked out the more obvious likely hurdles: constructing an acceptable extension to the steering, the shortening and balancing of a heavy-duty prop-shaft, making provision for weight changes fore and aft, and how, in detail, we would hold everything together structurally. Also, an all-important visual factor: would we be able to hide the more obvious bits of modern technology that could potentially ruin the finished article’s looks?
    We also had to be sure of the current availability of the specialist ‘30s style’ parts depicted on our plans and, where necessary, make acceptable changes. It was no good assuming we would somehow source the items from auto-jumbles and the like. If, as we intended, we wished to make more of our so-called supercars, we had to use readily available new parts wherever possible.
    Returning to the most important factor of all, ‘the team’, had we fully taken account of all the professions needed, and were we happy with those who had offered or been cajoled into joining? Jack, who in so many ways was central to the scheme, could obviously cover any intricate machining as well as much of the general engineering, while Bruce and Archie would keep an eye on the style. The indomitable Des, who continually informed us of his ability to perform miracles on any modern bodywork, was scheduled for the structural alterations, and Tom, with his modern-day Rover agency workshop, would be handling the mechanical work. A welcome addition had been the manager of a sheet-metal works, who assured us that no general fabrication or specialist bracketry would be too complicated for his highly mechanised outfit and excellently skilled staff. On inspecting some of their work, this was obviously true and instantly believed.
    Alan and his co-engineer, both and whom I knew from the work they did on our company’s exhibition lighting, quickly agreed to cover the electrics, adding that: “anything as simple as a motorcar could not possibly be a problem”. Rightly or wrongly, we believed them too. 
    We were short of someone for the interior trimming, someone who could cope with a modification that would in no way ‘look’ modified. Conveniently, both Des and Jack knew of a trimmer whose quality and attention to detail was second to none and, apparently, not too expensive. Would he, though, be prepared to involve himself in such an undertaking? With no guarantee one way or the other, we decided to presume that, when the time came, the challenge would be enticement enough – or that, at least, in those heady optimistic days, is what we settled on.

 

Page 36, para 2

    Based on what we now believed to be sound and well thought-out principles, the specifications for the completed car stated that: all the extras and special equipment should be retained, right down to the automatic dipping headlamps and even the ‘ding-dong’ seat-belt chimes. Furthermore, the car should be as reliable, maintainable, comfortable and as quiet as the original and, as testified in ‘Sidetracked’, that the drivability, handling and road holding should be as good, if not better than that prior to the conversion.
    Understandably, reactions were mixed. Some company shareholders were nervous, others non-committal and yet others thought the notion to be exciting and fun. Management and staff were more relaxed, with some, I suspect, even hoping it might keep me out of their way. Still, in the end, everyone agreed to this potentially profitable investment of a one-off prototype supercar for eventual intended production of between ten and fifty units.

 

Page 36, para 3

The SRH Hinge, the company’s patented ‘frictionless’ hinge, although in many ways quite basic and obvious when explained, has some rare and surprising qualities. The unique invention was featured on BBC’s ‘Tomorrow’s World’, which started a chain reaction of interesting and useful enquiries, a number of which lead to unexpected and, in some cases, very privileged meetings and discussions. 
    The company was eventually granted patents in all the countries where applied for, including the most difficult, Japan, with America even deciding to approve a ‘process’ patent as against a more tightly defined ‘product’patent.

 

Page 42, last para

    With the go-ahead given, we had to re-think every stage, section by section, item by item, evaluating all the plusses and minuses of a project fraught with potential pitfalls. Certainly one of our redeeming features at the time was ordering up all the specialist 30’s style parts as drawn on the plans, the lights, handles, hinges and other decorative exterior pieces. Any one of these might not be available when needed and, if not, would necessitate changes to what had been decided or even already done. In certain cases, it could have triggered a mildly disastrous situation, one resulting in a domino effect run of alterations.
    Of the structural modifications, we suspected the most difficult would be the narrowing and moving back of the bulkhead. On this, our only hope, while still being able correctly to re-attach all the necessary components, was to remove a section down the bulkhead’s centre that had nothing attached either in the engine compartment or in the cab. We would then re-join the two halves and move the result backwards to fit roughly where the front seats had been – not an easy task but something that, in our then state of rising euphoria, we thought perfectly feasible.
    On the other hand, the doorsills, the monocoque’s main strengths on each side lower down, were an unexpected bonus. They were positioned well inside the outer track of the wheels that meant they could easily be hidden under old-style wings and running boards. The same was true of the outer members of the front half-chassis. These ran back from the front wheels to just under the front seats and were quite straight and much closer together than on a normal full chassis.
    As for moving the engine backwards, feet not inches, there would very likely be problems with the narrowed bulkhead fouling the engine. Fortunately, whereas the position of the bulkhead and the position of the radiator were dictated by the style of the car, the engine itself only had to fit within the available space between the two. We soon discovered that, although tight, the engine with the  transmission directly attached, could sit slightly forward of the bulkhead, thus just clearing the obstructions of the air-conditioning on the one side and the steering on the other – another bonus.
    Mounting the engine and transmission further back without causing vibrations or any other mechanical negatives proved to be one of the simpler tasks. By re-using and shortening Cadillac’s constant-velocity double-Cardan joint  propeller shaft, we would have more leeway with the drive angles at both ends. The rear axle assembly would merely be put back where it had come from without any alterations, and any modifications needed to alleviate minor fouling of the transmission around the narrowed bulkhead tunnel would be made as required. Here, yet again, engineering optimism was quick to override engineering prudence – but, in truth, without a full motor engineering back-up, there was no other way.
    More of a challenge was how to design a forward space-frame to which the forward half-chassis could be re-attached, still using the three pairs of rubber-cushioned mounts. Two mounts were situated at the front of the detachable wings in line with the radiator, two more at the base of the bulkhead, and the rear two just under the front seats on the monocoque. In order to retain both the geometry and the legality of the vehicle, we knew that the half-chassis must, at the very least, be bolted back onto the two original rear mounting points, thereby retaining the original integrity of the Seville.
    To pick up the centre and front mounts, we would first have to construct a pair of tripods welded onto, and protruding forward and downwards from, the re-positioned bulkhead to pick up the centre mounts. Then, with further framework, we would somehow pick up the front two mounts. However, without a fully dismantled car, the final detail of this complicated bit of structural dynamics had to wait. Also, for all of our joint training, and for all the experience between us, I fear we were fast getting out of our depth – luck, once again, would likely play its part.
    That said, in the end, the answer to the front mounts lay in another pair of forward-pointing tripods, and hence the term ‘double-tripod’ space-frame. Unlike the first tripods, this pair would be long and thin with two legs welded onto the front of the cut-off doorsills running up just under the wings, with the third leg linking back down to the peak of the first tripods. Connected to each of the new forward peaks would be struts aimed downward, forward and slightly inward-pointing to pick up each of the forward mounts. Finally, partway down these struts would be brackets to attach the crossways headlamp bar, which effectively would complete the rigid structure across the front. Thus, when bolted in place, the only visible ‘stress-bar’ would be the one to which the headlamps and horns were attached.
    However, the realisation that the stresses on the three pairs of double-acting rubber mounts would now be entirely different threw us into overdrive. Using best, but sometimes short-circuited assumptions, we worked out which type of rubber isolators to use on each of the three pairs of mounts, forward, centre and rear; and, due to the stresses exerted being either upwards or downwards, whether to place them under or over the chassis brackets. In the end, when all done, this was one set of assumptions that, thankfully, proved correct and a potential catastrophe was averted.
    A final piece of the jigsaw centred on the half-chassis itself. By moving the engine off the cross-member between the front wheels and constructing the new engine support further back, additional stress would be applied to the rear legs of the half-chassis, especially on shock loading. To counter this, to the top of each leg, we added wedge-shaped strengtheners with their points facing to the rear. Although relatively thin, these effectively doubled the strength of the legs. Also, as explained in ‘Sidetracked’, we had to accommodate the rear transmission mount further back, and hence the need to design and fabricate the specially-designed backward-pointing A-frame.
    When it came to the forward-opening old-time ‘suicide’ doors, we had to decide whether to modify the Seville’s back ones or the front ones? Again, this was a decision that had to wait until we were able to dismantle one of each and fully check them out. In truth, as pointed out more than once in ‘Sidetracked’, we never really applied ourselves fully to this question, always fearing the worst and leaving it till last. Doors, as some of us had long since discovered, would always be trouble. Yet, in order to match doors to pillars, it soon became obvious that we should use the smaller rear doors, along with their matching centre pillars or B posts, in reverse on their opposite sides. Despite the inordinate number of hours eventually spent building up and modifying the front edges of these – as well as the associated locking device – this was the only way of guaranteeing a similar strength-to-weight to that of the rest of the painstakingly altered metalwork.
    The roof on the other hand, as partly explained in ‘Sidetracked’, proved a wholly unexpected surprise. By chance, the overall width of the Seville’s roof was such that, if cut-and-folded to imitate a look-alike soft top, it would fit straight back onto the rather more upright, vintage-looking pillars. Much to our relief, too, the height of our proposed four-fifths scale Roadster exactly matched that of the Seville. This meant, unlike the inept attempt all those years earlier, there was every indication that a driver and at least one passenger would fit inside!
    As for road wheels, we would retain the existing ones and merely fit suitable stainless steel covers to look like old-time wheel discs. We felt that modern spoke wheels would not look authentic, and there was never any thought of fitting old-style spokes, either for safety or drivability, to say nothing of the likely expense of the necessary additional modifications.
    Much of the other detail, including the necessary strengthening of the monocoque due to the removal of the outer sheet metal, had to be left until the outer metalwork had been removed. We knew that such strengthening would be possible within the confines of the new outer body design, but in no way could we plan accurately without seeing the bare shell.
    In truth, as several situations were later to prove, we were being more than a little cavalier in our approach. Still, in the end, as so often proved the case, luck or some other helping hand would ultimately come to our rescue.