The decision to build a racing version of a Lotus Carlton was taken in 1996.
At around that time I had become fascinated by a race that I had read about in an American Hot Rod magazine during a Stateside holiday. Having become disillusioned with circuit racing in the UK, after a shortage of the necessary money (and talent!) had failed to propel me to fame and fortune, I reasoned that a race held on largely straight roads and with competitors set off at 2 minute intervals should be much less likely to result in wallet crippling damage than the saloon car door bashing that I was used to. After an initial visit to the event in Nevada, and an entry the following year in a hire car, the American organisers encouraged me to come back in a British car “Something that we haven’t seen before”.
Knowing that ultimate success in the event would call for some seriously high speeds, the shortlist of possible cars soon became very short. I soon ruled out TVRs as being too flimsy and unreliable. A Bentley Turbo R briefly appealed as a suitably eccentric way to go racing, and scored too for its robust all steel construction. However, as a loyal fan of fast Vauxhalls, the choice soon became obvious. The Lotus Carlton’s blend of high power, efficient aerodynamics, and relatively mundane underpinnings won me over.
I had made some contacts at Vauxhall whilst racing a Nova, and approached them for help with my plans. None was forthcoming of course, but they did put me on to the boffins at Lotus who’d developed the car, so I was soon on my way up to Norfolk to speak with them. In fact whilst speaking to Lotus about my project, they had offered me one of their demonstrator cars, but they admitted that it had suffered a hard life, including salt spray tests and they wanted more money for it than I could raise at the time.
So then, long before the days of Ebay, I scoured the classified pages of Exchange and Mart, Motoring News, and Autotrader, and somehow found a breakers yard with about 6 brand new standard Carlton bodyshells for sale. By the time I got there, they only had 2 left and I eagerly loaded one on the trailer, looking forward to starting the build from an unused shell. Luckily soon after finding the shell the remains of a burnt out Lotus Carlton was found in another yard, which also yielded a new looking C36 GET engine. Apparently the yard concerned had bought the engine from a local Vauxhall dealer who was clearing out all their old stock, their haul also included five new C30SE engines! My engine had obviously been changed under warranty after delivery mileage. Inspection revealed that the under piston oil spray bar was broken in 2 places. A carefully rebuilt version of this engine was to be the race engine for my car.
The first job on the body shell was to decide the location of the fuel tank. We’d calculated that at the 6mpg we were told we could expect at sustained high speed, we’d require 120litres to safely complete the 90mile race. The engineers at Lotus also informed us, that any increase in fuel capacity would be likely to result in an overheated differential. Evidently, they had identified this in testing, but reasoned that the need to stop and refuel would give the tortured diff oil a chance to cool before any damage was done! As I wanted the fuel tank to be positioned where the rear seats normally are, to keep the weight centralised for handling and safety reasons, the enclosure for this had to fabricated as well as the rear half of the rollcage, so that the actual rubber fuel bladder could be custom manufactured to fit within them . Once the shell had returned from ATL the rest of the cage could be completed, along with integrated seat mounts and so on. As I was working on my own during evenings and weekends it took about a year to complete this stage. I had by then managed to find a replica body kit in the small ads of Cars and Car Conversions, (which for those that don’t remember, was a brilliant magazine for budding car modifiers like me). I would’ve liked a real kit, but they simply weren’t available without paying the dreaded 90393.… part number tax from a Vauxhall dealer. The fitting of the body kit was entrusted to Trevor Griffiths, who I knew through racing and was well qualified having previously built a number of highly modified Vauxhall based race cars. This saw the car returning to Norfolk, and Trevor’s contacts at the Lotus factory proved useful in securing the loan of essential body jigs to enable the shell to be updated to Lotus spec.
Another of Trevor’s tasks was to change the roof skin to one without a sunroof hole. However, before this could happen, I had to track down a suitable donor roof. It became apparent that since 1988 all UK sold Carltons came with factory fitted sunroofs. Also, even before then, only the 1.8L was generally specified without a sunroof. I found many 1.8s in breakers yards only to discover that they had either had aftermarket sunroofs added, or they had other cars stacked on top of them. Eventually another trip to the badlands of Essex yielded an unblemished roof, but only after a precarious encounter with a hacksaw, a carving knife and a balancing act on top of 3 other cars!
The challenge of building any car from parts, when you haven’t got a complete donor car to start with, is considerable. Try building a rare super saloon such as a Lotus Carlton from parts, and you soon realise just what a huge task confronts you. I had managed to find panels and some of the more basic mechanical items from breakers yards. I also started to find, that as word spread about my project, certain significant parts were offered to me, such as instruments, gearlevers and the like. Quite a few of these seemed to originate from the East Anglian region, and were almost certainly surplus parts that people involved in the original Lotus build had “put by” as souvenirs of their work. Some parts came as a job lot, and resulted in me finding myself with duplicates which I could then trade for items that I didn’t have. One lead for a potential parts source came through a work enquiry for my company to make exhausts for a new one make racing championship that was to be called “Formula Classic”. During my discussions, it transpired that two prototype single seater chassis had been constructed with Lotus Carlton running gear. The cars were deliberately designed to have more power than their skinny tyres could cope with, in attempt to replicate the spectacular racing seen before wide slicks and aerodynamics came to the fore. Evidently they had gone too far with the 3.6Litre twin turbo version, and toned it down to a 2 Litre Cosworth engine for the 22 cars that were built for the championship. Although most of the hardware had gone by the time I found out about it, this lucky break did yield the all important ECU, a Tech 1 diagnostic tool (complete with LC cartridge) , various wiring components and diagrams.
By this time the body shell had slipped deeper into Norfolk having been sent from Trevor Griffith’s Old Buckenham garage, to Pulham for the paintwork to be done by some more ex-Lotus employees. In hindsight I should have completed more of the build before painting, but I was filled with enthusiasm once I set eyes on the gleaming white body and panels. It’s amazing how much more real the car looked once it had a coat of paint on it. I’d even managed to gather enough parts to be able to roll it onto my car trailer on a set of slave wheels as I collected it from Norfolk for the long drive back to the Midlands to complete the build. At this stage progress seemed to dramatically slow down. All the big parts were in place, but as always it’s all the details which sucked up time and money as I reluctantly had to buy certain vital pieces over the counter. I soon realised that I was going to need help if I was going to maintain momentum. Although I am fortunate in my position of having a lot of good friends in the motorsport industry, I was well aware that, as it was their day job, asking them to help me build my car for nothing wasn’t going to happen. I also realised though that once I had engaged a couple of them, the work they could get done in only a few (long) weekdays, far outstripped my meagre efforts during evenings and weekends. Fortunately, building a racing car means that we could avoid all the niceties, such as air conditioning, ABS and soft furnishings. I had initially decided to try and retain the standard car’s self levelling air suspension. I reasoned that maintaining a consistent ride height through the proposed 90 mile race, during which we might consume 100kg of fuel, would be important to aerodynamic performance and rear tyre temperatures. However, it became clear that we lacked some of the control hardware, and therefore elected to run a somewhat simpler system incorporating adjustable rate dampers with fixed rate springs.
Second only to safety as the most important consideration in the build of the car was temperature control. Given the Lotus Carlton’s (slightly unfair) reputation for overheating coupled with the unrelenting heat likely in our desert destination, we spent quite a bit of time thinking about optimising the car’s cooling. Having failed to source any of the original oil coolers, Lotus’s supplier Setrab offered some slightly larger diagonal flow equivalents. These, coupled with removal from of the A/C condenser, improved the cooling capacity for the engine. Air flow through the radiators was also improved by adding more ducting to the side trailing edges of the bonnet (The eagle eyed may have spotted Astra GSi bonnet grilles, supplementing the OE LC ones). I also added the aforementioned electrically pump fed differential oil cooler, and a supplementary fuel cooler on the fuel return line. The latter was as a result of experience with a turbo charged touring car. The superheated fuel that was returning from the engine bay expanded the fuel bladder like a football, which we were keen to try and avoid!
Finally, on one memorable day near Christmas in 1999, while I was working at my factory I heard a rumble next door as the wiring guys decided to see whether the engine would fire up. Considering that this car was made up from parts of many different cars, it was a considerable relief when it actually came to life. There was still a lot to do, but after working through the Christmas break we finally put the first miles on the car at Bruntingthorpe airfield test track on New Year’s eve.
I am indebted to Dave Hirons who devoted his (unpaid) time and considerable energy to the project, and was only rewarded (!) with the opportunity of co-driving me twice through the desert in Nevada. Also thanks to Roger Smith who built the engine that never missed a beat.