THREADING THE NEEDLE

Brute force and precision are two elements you won't too often find going hand in hand and caked in mud at sactioned motorsport event

It’s a sport that simultaneously demands the brute force of a bull in a china shop and the delicate precision of an open-heart surgeon. When the two come together, the end result is a zero, and when they don’t — well, let’s just say it usually ends with a roll down a hillside or finishing half submerged in a mud bog. Welcome to the world of 4x4 trials. The sport requires the ultimate of both man and machine, with the crew of two tackling 32 hazards sprawled across natural terrain. Each hazard has sets of pegs dotted throughout it, consisting of three colours — blue, red, and yellow. Blue indicates the start and finish, red marks the right boundary, and you will find yellow pegs on the left. Crews start off at the blue starting pegs with a score of 100, and, as they progress further through the hazards, 20 points are deducted for every set of pegs they pass. If crews can edge their front hubs through the blue pegs at the end of the hazard, they score zero. The team with the lowest score at the end of the day is the overall winner. It is a simple concept, although winding your truck between trees on a slippery 45-degree slope, into a 90-degree right turn, and up a 60-degree incline without rolling end over end down the hill or running over the marker pegs, is no easy feat. It is like a ballet of brutality, with the rewards for clearing a hazard sweet and the consequences often brutally punishing. Tackling a sport like this requires a specialist kind of 4x4 machine, and, in the top class, there is no replacement for displacement. A good trials combination consists of three elements: a high power-to-weight ratio in the truck; reliability, as the trucks take a hiding all day long; and, finally, consistency from the driver and navigator. Being able to drive your truck to its full potential through all 32 hazards at a single event is extremely difficult. If you want to see a truck being driven on the ragged edge, then look no further than Scott and Jarred Biggs in their Roof Improvements Ltd machine. This truck roars in the mud and climbs like a mountain goat. The chassis comprises a custom-built chromoly tube frame, while the beating heart of the truck is an all-alloy six-litre LS2 pumping out 600hp — and that is before nitrous comes to the party. Putting power to the wheels comes courtesy of a modified Toyota Windom transmission, with four manually shifted gears and higher gearing specially paired to the weight and power of the truck. The hubs are Toyota Land Cruiser 80 Series components with chromoly CVs and Nissan Safari chromoly axles sporting hydraulic-locking differentials. These are bolted up to 15x12-inch Mickey Thompson alloy rims with OMF beadlocks, all wrapped in 35x12.5 Federal rubber. The 12-inch Fox air shocks are exactly that; they have been oiled and valved specifically for the punishing nature of 4x4 trials. With plenty of get up and go, being able to grind the truck to a halt is paramount, and braking ability is the point of difference between these trucks and other off-road machines. The truck sports

THE ALL-ALLOY SIX-LITRE LS2 PUMPS OUT 600HP — AND THAT’S BEFORE NITROUS COMES TO THE PARTY

Wilwood four-piston calipers all round, while Jarred, in the navigator’s seat, has four individual levers connected to hydraulic lines operating braking on each individual wheel, giving the truck the ability to brake and manoeuvre with inch-perfect precision. All of this muscle and finesse weighs in at a total of 1050kg. With oodles of power and plenty of stopping, working out how to tackle each hazard isn’t left up to the 4x4 gods and a bucketload of good luck. Crews have the luxury of walking the hazard prior to tackling it in the truck, giving them a chance to discuss lines, braking points, diff locking, and nitrous usage, but communication also happens on the fly. “Some communication while in course happens in order to get us onto our line, but usually it doesn’t go to plan and there is a lot of swearing and yelling to get the message across,” Scott commented. It must be effective, as the Biggs brothers have finished off the season second in the championship for the past two years, missing out on the top step by 0.98 of a point — yes, you read that right: 0.98. With hazards consisting of vertical climbs, off-camber cornering, deep mud holes, and speed tests, what appears to be guesswork is actually not quite a case of ‘point and squirt’. “The best courses require 100-per-cent calculation and sheer horsepower. Trying to keep the truck on line under full power is a real challenge,” Scott said. Deep mud and water aren’t just a challenge for the drivers to navigate; keeping the trucks going under such harsh conditions presents a challenge all of its own. “We use watertight electrical boxes to protect relays and fuses, while all the engine breathers are located as high as possible, due to the one-metre-deep water allowance on hazards,” Scott told us. Breakages are not uncommon in the sport, and, when you see how the trucks barrel into drops and up sheer, cliff-like inclines, you understand why. “It’s differentials, axles, and CVs that fail mostly with the huge loads we put through them. In extreme situations, transmissions and engines can let go as well,” he continued.