It shares a lot of cues with something like a pure Dakar racer, but built to a military-grade specification. The reasons being that the rules of the unlimited class are both simple and yet open to creative interpretation. The trucks must resemble a roadgoing counterpart, though only loosely. Underneath, they're essentially a war-spec spaceframe, triangulated for strength rather than lightness, because they need to be able to take the kind of pounding that would shatter a normal vehicle.
Bluntly, they appear impossibly heavy-handed when compared to the pared-back delicacy of most competition outfits. Fedor, for instance, weighs over 2,kg - definitely on the porky side. A Kroyer ci around 7. The class doesn't allow for any sort of power adders, so no forced induction or nitrous oxide injection.
But, even so, Fedor's V8 runs to bhp with lb ft of torque. This is mainly because the reinforcement needed to keep the thing running in race conditions means that it becomes a kind of giant torque-converted black hole for engine grunt.
In the middle sit a driver and co-driver. There is no glass or Perspex in the windows, because windows in a Trophy Truck would have the life expectancy of a depressed mayfly. Behind the cabin is a gallon fuel cell, and behind that sits a piggybacked pair of the giant spare wheels, positioned rearward for two purposes: accessibility and balancing the truck's nose-heavy stance.
Trucks could happily cope with much more power - BJ reckons way north of 1,bhp would be perfectly practical, except for the fact that those kind of numbers consume fuel at a rate impossible to balance against the requirements of endurance racing. When you hear that BJ's current engine only does 3.
Oman, basically. But the power is nothing like the whole story, merely the first chapter. Because, more than anything else, these vehicles are defined by their suspension. Their ability to take thousands of tooth-rattling punches and still drive for 12 hours. The dampers themselves are faintly ridiculous, nearly four feet long, manufactured by a company appropriately called King Shocks. They feature remote reservoirs and easily tweaked compression and rebound.
If you see a video of them moving across the ground, it's like watching the proverbial swan - peaceful from the waist up, paddling like crazy underneath. The stats are formidable. The front wishbones can manage some 26 inches of independent travel, the rear three-link solid axle around That's an unholy amount of fast-reacting suspension swagger. It's probably worth pointing out here that this information comes to you courtesy of autonomous note-taking, because essentially I wasn't listening during the entire briefing.
Too excited. And, eventually, after an eternity of careful preparation, we plonk Fedor and a chase truck onto a couple of trailers, and head out in the desert. To drive. This is more like it. A bare hour outside of Vegas is BJ's test area, and the kind of scenery I'm more used to seeing Trophy Trucks batter their way across. A huge salt pan surrounded by tracks and trails wound through scrubby, sharp-looking desert and ground-hugging foliage sporting the kind of spikes usually found on medieval armour.
The sun is degree hot, but I'm the one who's about to explode. Safety first, and it takes an age to get suited up, fix HANS devices and tighten belts. Hoses and lines are attached to my helmet - one for comms, one for piped, clean fresh air - and Fedor's virtually unsilenced V8 fires up. It sounds like a drag car, guttural, phlegmy, fan-bloody-tastic. Hook first from the manual auto there's no clutch, but you still shift the gears yourself on a linear shifter and pull away.
Fedor, as it turns out, is surprisingly easy to drive. Build some speed on the flat, shift to second with a slur, and then third. We won't see first again until we stop. The steering is eerily quick and totally numb, the enormous power assistance needed to stop drivers ending up with forearms like tree stumps with thumbs. Feet are clasped in little metal shoes that sit over the two pedals, there to stop your feet from bouncing on and off the controls when going fast over rough ground.
BJ is talking to me, telling me to go faster, not to be afraid of the bumps. Only they aren't bumps. They're more like midget mountains. Obviously, not wanting to look like a wuss, I gun it. All hell breaks loose. The experience is like nothing else. Acceleration is forceful but not daft, and accompanied by the front rearing like a speedboat.
Trophy trucks are built with the aim of being the ultimate off-roaders, and it shows. There has historically been some debate about what determines the most difficult kind of engine to build. Engine Builder Magazine suggests that the previous champion was the mills fitted to offshore powerboats. These are engines that are constantly tilting along the X, Y, and Z axes, propellers lunging in and out of the water, all while viciously bouncing up and down like a kangaroo on PCP.
Add that to the sheer power demands and you have a very difficult piece of machinery to keep running. However, trophy truck engines might just beat them out. Trophy truck engines need to make a lot of torque , and they need to make it across a very broad power band because of the wide variety of speeds you might hit in a race: anything from rock crawling to doing mph down a wadi.
All that power makes them very thirsty for air, and many of the courses they run most notably the infamous Baja races are absolutely choked with dust, which demands high-quality filtering. The engines also need to be able to run on full throttle for hours, which also necessitates massive gallon fuel tanks to compensate for the mpg they manage.
Trophy truck suspension is the stuff of legends. Generally, there are two shocks up to 5. The springs can get at least two feet up to nearly a meter of travel, complemented by huge inch tires that can weigh up to lbs due to their reinforced sidewalls. Of course, dirt ingestion is a natural part of off-road racing that builders need to account for, and engines need to run for a long period of time without burning too much oil while remaining cool enough for optimum power.
Common failures can also occur if the engine builder has put more thought into horsepower than the longevity of the engine. To finish first, first you must finish, is the common mantra. Many engine builders utilize a variety of different engines depending upon the series and the customer.
Some engine builders, like Dougans Racing Engines, rely on custom components for engines, electronics and all accessories. The connecting rods we use are designed custom to meet all of our needs.
Pistons are a constant evolution. We install all of our own valve guides and valve seats in our latest big block programs and we complete all of that in-house. Everything is custom. In addition to the components, these engines have to be tuned properly to perform their best. The relationship of horsepower to torque in a lot of racing is all about the horsepower, but torque is really what moves the vehicle forward.
After the hundreds, and in some cases, thousands of miles of racing and the many hours of engine development, the most important aspect of building a trophy truck engine is watching your efforts translate into a win and your customer celebrating atop the podium. Features: Justina Reusch, Reusch Diesel. Magazine Current Issue Past Issues. Connect with us. Advertise Subscribe Contact Us.
ICE vs. Compound Turbo 5. By Greg Jones. Why Building Successful Trophy Truck Engines is so Damn Hard Trophy truck engines have surpassed hour endurance race engines and offshore powerboat engines as the toughest engines to build due to the insanely harsh environments these vehicles race in.
Photo by Daniel Schenkelberg Ten years ago, building an offshore powerboat engine was considered the most demanding job ever; Hands down.
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