All That Glistens

Originally Published: June 2012 Words: Glyn Bardsey Pictures: Steve Taylor

$If you’re not already gazing at this picture and nodding your head in approval, you should start now. With the radiator in the back, the space behind the winch is occupied by AlliSport’s new charge cooler – a water-to-air intercooler which is ideally suited to challenge trucks as it continues to work even when the engine’s toiling and the car’s only moving at fractions of a mile per hour$

The radiator for the charge cooler is located behind the driver, out of the way of flying mud and, as much as possible, branches and other undergrowth that could damage it. Like a conventional water-cooling system, it runs to a header tank to ensure it remains full – this seen above it, linked by wide-bore silicone hoses

The Whitbread frame provides mounting points for Discovery 2 front radius arms at both ends. These are used as they’re longer and stronger than the Defender version, and have bigger bushes. The familiar Defender-style location layout is used, with a panhard rod at the front and A-frame at the rear

A large skid plate underneath the frame allows the 100” vehicle to slide over extreme breakovers, but what’s really notable here is the pair of small-bore pipes running along the main frame rails. These are water pipes linking the rear-mounted radiator to the charge cooler up front, the whole system being driven by a small pump in the driver’s footwell

The pipe at the top of this picture comes in from the main air intake (which is mounted behind the navigator) and swings back round, via as wide a knuckle as possible to allow a smooth air flow, to feed the turbocharger. Hot air from the turbo then runs forward to the charge cooler and on to the inlet side, where it enters the engine at a consistently low temperature. This is important both to prevent dangerous heat build-ups and to maintain the density of the charged air, and thus the performance achieved by the engine

Mike describes the exhaust manifold as ‘genuinely a work of art,’ and when you look at this you can’t help but agree. He’s not being immodest because he didn’t make it – it’s yet another AlliSport product being pioneered on his vehicle, and the good news is that if you want your TD5 to look this sexy, sales are now fully up and running

The main radiator for the engine cooling system (as opposed to the charge cooling side) is just inboard of the rear winch tray. Another piece of AlliSport magic, it has air drawn through it by a Spal fan and sits in a bespoke cowl. The system runs a custom header tank, mounted remotely next to the centre winch, and is plumbed throughout in alloy piping and silicone hoses, with the standard TD5 thermostat controlling the flow of coolant

Like many vehicle builders, Mike was attracted to the Discovery 2 power steering box because of its big, thick sector shaft. While this is indeed very strong, however, the weakness is merely elsewhere instead as the roller is prone to punching through the worm gear under high loads. Ultimately, he’ll be swapping it out for either a Japanese unit or a hydro-assist set-up

37x12.50x15 Maxxis Creepy Crawlers provide immense grip and similarly immense ruggedness. Allowing them to be run at low pressures is a set of beadlocks welded to the otherwise bog-standard 8x15 steel rims

Both axles are 24-spliners containing standard 3.54:1 diffs with ARB lockers. The front unit has been pegged for extra strength and runs out to Roving Tracks shafts and CVs, while the rear contains GKN halfshafts. The rear A-frame is clearly visible here, providing the articulation for which three-link location is famed

You see trucks with jaw-dropping amounts of articulation, but here it’s designed to be effective rather than pointless. Doing the work is a set of 7/8” Fox 2.0 coil-overs, combined with hydraulic bump stops from the same manufacturer, which provide 12” of travel at each corner

Having seen other vehicles struggle on events because their fuel filters were hard to get at for servicing, Mike located his beneath the driver’s seatbox. This means it can simply be unscrewed by hand, though of course it’s also more vulnerable – which is why he’s planning to put some protection in front of it before King of the Valleys

A challenge vehicle is only as good as its winch, they say. And they should know. Which would makes this a very good challenge truck indeed. Tucked well back and mounted on one of the trays that are integral to the Whitbread frame design is a Warn 8274 with Gigglepin’s twin-motor conversion. When we took these pictures, it was running a pair of 12-volt XP motors, but Mike was already planning to convert it to 24-volt with a pair of Bowmotor 2s in time for the new season

By comparison to the monster on the front, the rear winch is a straightforward Goodwinch 9.5i. There’s another of these in the centre of the vehicle, mounted behind the cab; both run Albright solenoids to help fight off the water that regularly ends up sloshing around them

The cabin of a challenge vehicle is no place for frills, so you won’t find any here. Essential fuses, for example, are simply mounted as high up as possible to keep them away from water, and the cables from it run down the middle of the windscreen to a basic console for the diff-lock and winch controls. Fiddle brake levers don’t count as a frill, either, even if their heads are the most colourful thing in there

All that glistens is not gold. In this case, it’s mostly aluminium. That’s because Mike Robertson’s challenge buggy is more than just a top example of what you can do with a Whitbread tubular frame – it’s a rolling test bed for AlliSport’s latest and sexiest products

Every self-respecting off-road vehicle build ends up taking longer than expected. And Mike Robertson’s 100” tube-framed challenge truck is no different.

But while the average project usually drags on by years, often before being given up on and sold for parts, Mike’s only ran over by a few months. It was meant to be ready for the end of September 2010, but finally turned a wheel in mid-2011.

It’s fast, you see. That’s what comes of being light. And of sporting various trick bits which, if you read on, you’re going to want too.

How do we know? Because we wrote this, didn’t we, and we want them. It’s not every day that a company like AlliSport comes out with something totally new, and when it’s something as revolutionary as the kit on Mike’s truck, it’s time to pay attention.

The truck itself is a Whitbread Off-Road 100” tube buggy. Mike was working for the company when the build started, and the vehicle itself featured on its stand at the 2010 British Indoor 4x4 Show. Back then, it was just a rolling frame, but things have moved on since.

Mike knew he wanted a purpose-built challenge truck after growing out of the 90s he had campaigned previously. Having taken part in his first RTV all of two weeks after passing his driving test, he’d fallen into comp safari racing in a friend’s V8 truck-cab then started doing driving days, where he liked the idea of not being restricted to existing tracks.

Seeing videos shot at the late, lamented Tom’s Farm added fuel to the fire, and when finally he clapped his eyes on a set of Simexes round the back of a mate’s house, he knew what he had to do. Build a vehicle for challenge events, that is, not nick his mate’s tyres.

The vehicle in question was a ‘poverty-spec’ 90 with no cage, no strengthening and standard suspension. And the event in question? His first ever, the Tay Forest Challenge – possibly the toughest of its kind in all of Britain. ‘We didn’t finish last,’ he recalls with pride, ‘and we drove it home afterwards.’ Not surprisingly, the experience taught him a lot. Mainly that he needed a better 90. By the time he showed up for his first challenge at Manby, he was running big Simexes and Warn 8274s all round. But, in his words, ‘it was still a big, fat 90.’

‘Big’ and ‘fat’ are not words you normally associate with Land Rover’s most diminutive product, but there you go. In Mike’s group at the event were Chris Abel and Simon Wilkinson, who at the time were still using a 200Tdi Range Rover, and so the whole weekend basically turned into a masterclass.

‘They could have laughed at us,’ explained Mike, ‘but he came over and told us what to do, and we found that it worked. It was a really important event for us, mainly because we learned so much from it.’

More learning came at the Muddy Truckers, and this time the lesson was that his 90 was ‘a big, soft panelled car.’ Those panels, every one of them, were reduced comprehensively to scrap, so he started protecting the vehicle with tube – until it ended up even bigger and, though no longer as soft, now so heavy it was basically useless.

He’d already spoken to Malcolm Whitbread about building one of the company’s very popular challenge buggies, so once he was actually working there it was only a matter of time. What his unusual position of being a customer as well as an employee meant, though, was that rather than speccing the vehicle to suit what he already had, he could go ahead and build it exactly the way he wanted it to be.

To cut a long story short, that meant a TD5 engine and five-speed manual box from a Discovery 2, mated to a 1.4:1 Defender transfer case and strengthened 24-spline axles with ARBs all-round. The engine is fitted with a VNT turbo and roars out an estimated 200bhp – enough, in Mike’s words, to ‘make the hairs on the back of your neck stand up’ when you give it the berries.

But that’s not all. We mentioned the AlliSport connection, and Mike has a tie-up with the company that’s seen it use his vehicle as a hardcore test-bed for a variety of spectacular new products. The merest peek in the engine bay, for example, is a feast of gleaming alloy and tidy silicone hose. What you’re looking at, if you can draw your eyes away from the ultra-sexy five-branch exhaust manifold for just a minute, is the business end of a water-to-air intercooler.

This is an exciting development for lots of reasons. Principally, though, it solves the problems you get with the traditional air-cooled system turning into a large heat-sink when clogged with mud or operating under heavy load at very low speeds – both things that tend to happen rather a lot on challenge trucks.

The system starts with a custom intake pipe which routes air from the filter to the turbo. This is a wide-bore affair with the sharp angles designed out, and its all-aluminium construction means there’s no danger of it failing to stand up to the demands of an over-sized turbine.

Beyond the turbo, in the void ahead of the engine where the radiator would sit on a standard TD5, is the charge-cooler itself. This gets cold water from a fan-assisted radiator behind the driver, using it to cool the charge of compressed air from the turbo.

‘As long as there’s water in the charge cooler,’ explains Mike, ‘the cooling efficiency will always be approximately the same no matter what. From the testing AlliSport did, the outlet from the turbo was over 120 degrees and the inlet to the engine was sub-30. This was measured with the vehicle stationary and a high idle speed for 3-4 minutes, as if we were retrieving the ropes on to the winches.

‘Having driven it at speed, there’s a definite improvement over what we had before. Even once the engine was at full operating temperature, the water in the charge cooler system was never more than lukewarm.’

The cooling system, as opposed to the intercooling system, is also from the AlliSport portfolio and was bespoked for this vehicle. Located at the back of the vehicle, just inboard of the rear winch, is a high-spec aluminium radiator, with a Spal cooling fan mounted to bespoke cowl. A remote header tank is located next to the centre winch to keep it out of the way and the system is plumbed throughout in alloy piping and silicone hose, with the original TD5 thermostat controlling the flow of coolant.

All this arrived after the vehicle had been shaken down in its first events, and not a moment too soon. Because what had happened first time Mike took it out to play? It had overheated, that’s what. ‘We literally got it finished on the Friday night and just put it on the trailer, and typically of a rushed job we had masses of cooling problems from air locks. So we spent most of the Saturday fixing it, but then by the Sunday night we were up to eighth overall – even with a badly slipping clutch.’

Now, with more events under its belt, the vehicle is getting towards being sorted, and with King of the Valleys on the agenda that’s no bad thing. Even so, 2012 will be its first full season, so it won’t be until the end of this year that Mike’s ready to decide if it’s up to the sort of events he has in mind – namely Croatia, Ladoga, and most of all the infamous Dresden-Breslau. Not an event that gets much attention from UK off-roaders – but with a few more high-profile entrants, that could change.

Talking of changes, the arrival of all this top-notch and very wantable AlliSport kit shows that even this soon after getting the vehicle up and running, Mike is willing to do whatever it takes to improve it. When we took these pictures, for example, he was halfway through fitting a set of Fox hydraulic bump stops (only the rears were in place), and he was planning to replace the 12-volt XP motors on the front winch with a 24-volt Bowmotor 2 set-up.

On top of this, the learning never stops. Mike admits that he was seduced into using a Discovery 2 power steering box by its big, strong sector shaft. But in keeping with a lot of people, he’s since found that while these rarely give trouble when used the way Land Rover intended, on more extreme vehicles the roller can punch its way right through the worm gear. By the time he ever takes it to Breslau, it’ll be running either hydro-assist or something Japanese.

Nothing major there, though – just the constant fettling it takes to turn a good truck into a great one. As it is, Mike has put his days as the driver of a ‘big, fat 90’ well in the past, and with the Whitbread frame allowing his vehicle to weigh in at just 1850kg in full competition trim, he’s very much ready to take on the top boys.

There are vehicles built to look more show-stopping than this one, and to blow you away with the sort of articulation most people admit you don’t actually need, but there’s no doubting Mike’s 100” masterpiece is one to watch. And if you get the chance to gawp under its bonnet, take it. Just don’t be surprised if you start dreaming about aluminium soon afterwards.

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