Anyone who has driven major highways knows how intimidating a semi truck can be. They roar and crash along the pavement, the exhaust brake popping and growling, slipstreams causing their smaller gas-fueled cousins to sway and rock in their wake. They are powerful and sometimes awe-inspiring machines to witness in motion.
It's those same qualities, plus their familiar and mundane presence, that makes them appealing as a race vehicle. While race trucks will never haul a load of washers to the local big-box appliance store, they still retain many of the same characteristics as road-going brethren.
European super trucks, encompassing the United Kingdom, the European Union, Australia, New Zealand, Brazil and China, race under the broad umbrella of the FIA, or Federation Internationale de l'Automobile, the French authority that also supervises the Formula One series. The FIA mandates strict regulations including super trucks retaining much of the equipment standard to the everyday hauler, including a standard diesel engine. But the race trucks are allowed to tweak and tune those engines to dance to the beat of a very different, and all together faster, drummer.
The race trucks are limited to a 12-liter diesel engine. When the sport first got its start in the 1980s, beefing up the engines meant adding turbochargers -- the bigger the better. As technology has changed, and engine management software has replaced brute force with finesse, most race trucks sport software that manages engine power and torque with algorithms and advanced math rather than mechanical crudities.
What all this boils down to is the software allows a savvy diesel engineer to tweak the air-fuel ratio in literally every cylinder to produce more than 1,000 horsepower and more than 6,000 pound-feet of torque (8,135 newton-meters) from a standard engine.
This power is handled by the transmission, which makes use of modified gearing for performance. In the United States, Allison transmissions dominate the market, but outside of our shores, ZF transmissions rule the road.
ZF was the main medium- and heavy-duty maker for over-the-road transport and became the main producer and supplier of racing transmissions during the sport's height in the mid-2000s. Similar to their more mundane street-going cousins, the racers use a manual transmission; however, again, various electronic and mechanical tweaks are added to the system to give better performance.