www.engineeringnews.co.nz 9 cars who did most of the work. “I studied all the existing bodywork so that I could basically reverse engineer a modified piece of 1970 customer bodywork back to an M8A. From moulds of the old Trojan customer cars that Group 7 have bought and own in England, I started with an M8C front and an M8E rear and we made a panel out of each of them and then started modification.” Looking at the front of the new buck – the front upper section was M8C, the next section piece was off an M8D and then the other section was from the M8F. “It is just a matter of identifying the componentry and using it with unmolested pieces of various bodies and putting them all together,” says Fox. “Finding pieces of the body work became a saga in itself. It would have been unexpected that we would find any M8A panels in America because both the A cars went back to England. If we were ever going to find A bodywork it should have been in England and not in America because there are no cars there that it would fit.” However, on one of his trips to America, Fox discovered that a piece of M8A bodywork had been sold in America. Apparently it was used on a tube frame car in the San Francisco Bay area. “Then it was just a case of heading for the bay and finding old timers who ran a car that looked like a McLaren,” says Fox. “I tracked down a car and followed its movements, and then came to a dead end, only to find one piece of body work but not recognising it.” Because it niggled him for a year, on his second trip back, Fox followed it up again and found the piece of bodywork sold in 1973. The McLaren team had left the bodywork with Motschenbacher because he was the agent and they figured that he may be able to sell it in California, rather than having to take it back to the UK. The rear wings are another fascinating story – the rear wings on an M8A were unlike anything else used on any other car, either a works or a customer car. “It was one of the things where we knew what it looked like from the pictures but we didn’t know how to make them,” says Fox. “It turned out that the wings were one of the first pieces of bodywork that we actually acquired.” Fox managed to track down a guy in Los Angeles who had dug the fire blackened and burnt wings out of the dumpster when they were cleaning up the Motschenbacher workshop after it had caught fire. “These two pieces of wings and sides were quite charred in some places but if you study them hard enough you can almost see the plywood - and that’s how they were made, on a plywood buck,” says Fox. “By a bit of ‘carcheology’ I decided that these particular two pieces of wing probably came off another body panel. We know it didn’t come off the body panel we had as the holes didn’t match. However, we do believe that they came from Bruce’s car rather than Denny’s because they were in two pieces, as carried from the UK as hand luggage on the plane.” The bodywork alphabet soup gets a bit complicated. The M8C front, the upper portion was the same as the M8A but the radiator duct opening was different because the C body went on an M6 chassis and not an M8, so that portion had to be altered as the M8A radiator was narrower. “The C dashboard has a large hump in it, so we had to get rid of that and this all took hours of studying pictures, reading books and just looking at the body and absorbing it all,” says Fox. “I knew that an M8E front was made from an M8B, so it was a natural progression, but because it was an understeering car, they quickly modified it before they sold the customer cars,” continues Fox. “One bit of information I got was that the front of the dash was always going to be constant, B, A or E. So I knew that by cutting the front off the dash, I had the front of the dash for our A. The D dash was different, but originally I thought all I had to do would be copy the D dash but it was much higher. Then I had to find in the piece of E body panel, the section where it changed, where they had filled in the old panel. So then I grafted the E piece into the new body and then hand made the radiator opening.” “On the C the windshield was up much higher, there’s a lip, a ledge at the bottom so all that had to be dropped, because the top of the dash followed right through to the screen This was hand made and taken from an F body,” says Fox. “The front alone tells a huge story, but once we got it to this point, we could identify the line that they made the original bucks off. We made moulds of the B body and then cut all that stuff off, put the D mounted pieces in, then made the A fenders by basically cutting, fiddling around, and adding pieces on. All you have to do is ask, “why did they do that?”, and then reverse engineer it all. During every step of the restoration process, the project was under the control of one of the Trustees, Duncan Fox, who is an experienced engineer and owns Group 7 Sportscars Ltd, a company dedicated to restoring McLaren racing cars. The Trust was able to utilise Duncan’s skills in conjunction with a set of original McLaren factory drawings to ensure the restoration project was completed to produce a safe and authentic McLaren M8A. Several engineers and mechanics that worked for McLaren Racing are now resident in New Zealand and have also volunteered their services and knowledge to assist with the rebuilding. Research – Extensive research has taken place over the last eighteen months to evidence the car’s history, its pictorial history, procurement of original plans, the availability of components, body moulds and general requirements. Monocoque – Aluminium to match the original material was sourced from the USA, original rivets were sourced from the UK and new steel bulkheads have been built. Once the monocoque had been reconstructed, a number of mechanical components were replaced – these included replacement of the magnesium suspension uprights, wheel rims, etc. These require replacement because the magnesium alloy has a finite working life and then becomes prone to stress failure. Moulds were produced using the original pieces and these components have been manufactured. Engine and gearbox – The engine and gearbox required complete replacement, as the ‘dummy’ gearbox and engine in the display car was just a ‘grenaded engine block’ and empty transaxle. A number of vital small missing components were also manufactured from original factory drawings. The Trust had the option of installing an aluminium or cast iron 427cid Chevrolet engine of approx 600bhp. The cast iron option was chosen, as it would be a much more ‘user friendly’ engine in terms of reliability. The original aluminium engines were built for lightweight performance, but not a long life! The gearbox is a Hewland LG500.
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