Geek Out! Kicks like a mule

Of course, mules don’t exist to create intrigue, they have a practical purpose to save time and money. As soon as the fundamentals of a new model have been established, it’s often useful to get cracking with physical testing, even in an age of mighty computing power. For this to happen, an engineering team can wait for the first representative prototype bodyshells to be made from soft tooling or they can take a short cut. Which is to use the skin of an existing car, bent as necessary to accommodate those engines, suspensions and electrical systems you want to start testing. And so the mule is born.

Within the mule world, however, there are different species. One of the most commonplace is the current model giving an early shakedown for its replacement, which will be based on the same platform. Car evolution being as it is, the new one is going to grow a little bigger so the mule might be a standard-looking example of a car we know, given away by wheel arch extensions to cover a track width expanded beyond the bounds of the existing shell.

Things get more interesting if the next model is going to have a longer wheelbase because then you get surgery to the shell and possibly some of the proportional weirdness that makes mules so intriguing. The most extreme examples of this in recent times were the mules for the current Land Rover Defender which were made from Range Rover Sports, since that car uses the same basic platform, but comically truncated for Defender 90 test cars and unnaturally stretched for the 110 chassis. Perhaps unnecessarily, Land Rover treated these mutants to an all-over camo wrap, though this is not uncommon when wheelbase altering shenanigans are afoot to make it harder for the product planning people at rival car makers to estimate the dimensions of your next big seller.

To my nerdy eye, mules get even more interesting when there are all-new parts underneath rather than a carryover platform. For example, when Saab started developing the all-new 99 in the mid-1960s, its engineers grafted the mechanical bits of the new car under the shells of its current model, the 96. Except, the 99 was going to be significantly wider than its predecessor, so four 96 shells were sliced front-to-rear and widened with 20cm strips of metal. Their new, broader faces earned these cars the uncharitable internal nickname Paddan, Swedish for toad, but in isolation they looked plausibly like any other 96. The game was up only when one of the mules was spotted in convoy with a normal 96, giving an unwelcome sense of perspective.

When Ford started putting road miles on the mechanicals of the all-new Sierra by grafting its parts under Cortinas, the ruse was betrayed not by a radical change in proportions but by the new semi-trailing arm rear suspension in place of the Cortina’s live axle which looked so visibly different that these mules would be flashed by following motorists thinking this scruffy Ford’s chassis was in the middle of catastrophic collapse. The development engineers quickly got round this problem by having Sierra mules tow trailers to conceal the new parts on test.

These are still quite subtle examples of the art, mind you. The real fun starts when the base vehicle is of a totally different kind, as happened in the 1990s when Rover wanted to start proving work on what would become the MG F. Since this car had no predecessor to modify for test work, the mule makers got creative and installed the mechanicals for their future mid-engined roadster beneath a small fleet of Austin Metro vans. One of these mules survives to this day in the British Motor Museum, still wearing signs on its doors advertising a made-up delivery company.

Soon after its MG F caper, Rover excelled itself again when it began shakedown work on project CB40, the car we know as the first Freelander, which was undertaken using a fleet of about two dozen jacked-up Maestro vans. The only backfire here was the occasional call Rover would receive from a member of the public who had spotted one of these machines in the wild and wanted to know where they could buy one.

For real mule nuttiness, however, you can’t beat the current Corvette. This car was a big deal, what with the shift to a mid-engined layout, and early in the project engineers wanted to get moving on physical testing. So, in the name of throwing spies off the scent, they got hold of a Holden Maloo, the ute version of the Commodore saloon, and broke out the saws. As a result, the first testbed for GM’s exciting new mid-engined sports car flagship was built out of an Australian pick-up.

Actually, that’s not entirely true. The nose and cargo bed were from the Holden but the cabin section was lifted from a C7 Corvette and there was a huge, extremely non-standard wing at the rear, plonked on top of a thick bed cover which concealed an unexpected V8 in the bagging area. Just to complete the picture, the whole thing was painted in an inky monochrome, earning it the nickname Blackjack. All this subterfuge only went so far, however, because in 2015, five years before the C8 was announced, Blackjack was papped by an ambitious spy photographer in a helicopter swooping over GM’s Michigan proving ground and his pictures spread far and wide, accompanied by stories accurately guessing that a mid-engined Corvette was on its way. The Blackjack was still a spectacular mule, even if it didn’t do much to stave off the rumours. If anything, it just heightened the intrigue, and intrigue is what makes mules so fascinating.

Which brings me back to that mystery Audi spotted on the lanes of Norfolk in 2007. Usually when a mule gets papped the truth about what lies beneath its stitched-together skin eventually emerges. But with this hacked-up A8, nothing ever seemed to fit. It was unlikely to be a Lotus, since if you were doing early work on a small, fibreglass sports car you’d hardly start with a large, aluminium limo. More probably it was someone else’s project, sent for some early polishing at Lotus Engineering. Lots of car companies do that, more so than we’ll probably ever know.

But which car firm had come up with this one? I couldn’t rest until I found out. I started asking around everyone I knew in the car world who might have a clue until eventually multiple sources came back with the same answer; that weird A8 mule was actually a Bugatti. Specifically, some ill-fated scheme for a second model to sit below the Veyron. The project seems to have floundered for many reasons, not least that it would have to live in the shadow of the most ultra car in the world, and we have to presume that once it was cancelled the poor A8 mule went to the great proving ground in the sky. Which is a shame. Because, by being both mutated and mysterious, that old Audi was an absolutely brilliant example of everything I love about a test mule.

If you want to make me seem less strange for having favourite mules, feel free to nominate yours in the comments below.

Thanks to The Dunsfold Collection for the Freelander Maestro van images. Remarkably, it has two of the three remaining mules in its collection