Competing at a weight of 6200 pounds, this division carries a likeness to the “funny car” division of racing with their lengthened wheelbase and flip up fibreglass bodies. Powered by a maximum of a 575 cubic inch V-8, they are limited to a 14-71 supercharger for air induction. This class is also offered on the NTPA schedule. Plenty of noise and front wheels in the air for most of the run, these vehicles are often steered with rear wheel brakes to stay straight!
Super Stock 4X4 Trucks
Competing at a weight of 6000 pounds, this division carries a relatively stock body appearance. Limited to a 526 cubic inch naturally aspirated V-8, this class uses a maximum of a 35” tall DOT approved tire that cannot be custom cut or altered in any way. An exciting class that relates to most people based on their street truck like appearance.
Hot Farm Tractors
Competing at a weight of 8000 and 9000 pounds, this is truly the entry level class for those looking to get involved. With limitations like 410 cubic inches, 3100 rpm limit, and turbocharger size limits, it allows an individual to take a genuine farm tractor and alter it to enter the class. The absence of roll cages and aluminum wheels with puller tires keeps these tractors looking like their field working brothers. These same tractors have also competed at 10 000 pounds.
Light Limited Pro Stock
Competing at 6500 and 7000 pounds, this was originally created as an entry level class. It has evolved over the years into a very competitive division. Limited to 410 cubic inches and a 2.5” turbocharger inlet size, the light weight of these tractors make for an exciting class. A mix of diesel and gasoline power makes for an interesting twist.
Limited Pro Stock
Competing at 8000 and 9000 pounds, this class is the big brother of the Light Limited Pro Stock. Limited to 515 cubic inches and a 3.0” turbocharger, this division is generally powered by diesel fuel only. A nice mix of manufacturers and colour make for an interesting class.
Competing at 9300 and 10 000 pounds, this is the heavy weight class offered. Limited to 640 cubic inches and 3” inlet/outlet turbocharger, this division is all about muscle! With horse power approaching 1300 and torque at nearly 3000 foot pounds, these guys are serious. Fractional inches often separate these competitors making for an exciting class. Also offered on the NTPA circuit, this division will see many different competitors over the season. If you like black smoke, this is the division for you!
The Pulling Sled
In the early days, either a dead weight of fixed mass was dragged, or the step-on method was used, which people stood at fixed positions and stepped aboard as the sled passed. Today’s sleds use a complex system of gears to move weights up to 65,000 pounds. Upon starting, all the weights are over the sled’s rear axles to give an effective weight of the sled plus zero. As the tractor travels the course, the weights are pushed ahead of the sled’s axles, pushing the front of the sled into the ground, synthetically creating a gain in weight until the tractor is no longer able to overcome the force of friction.
The sled can be adjusted in many ways to create a desired pull. Weight can be added or removed from the box. Adding weight on the pan can give more starting weight to the pan of the sled. The box gearing can be changed to move faster or slower, and the starting position of the box can be moved among a two feet area, affecting the distance of travel. The final adjustment is the placement of the trip, which applies the push down system to expend the full weight of the sled on to the pulling vehicle.
- Box – Contains the weight used to stop the vehicle and moves up the length of the sled rails progressively during the pull, driven off the front set of sled wheels.
- Weight Block – Most sleds use a “full block” that weighs 2,000 pounds and a “half block” weighs 1,000 pounds.
- Pan – Applies the force of the weight to the ground creating needed friction. The sled starts with only the front of the pan touching the ground. Bars attached to the bottom of the pan help make added friction at the end of the pull to stop pulling vehicle.
- Trip – Sits between the frame rails of the sled. As the box moves up the rails the trip is hit and starts the push-down system. The trip is adjustable.
- Push-Down System – Uses hydraulic cylinders to lift the back half of the sled in the air, allowing 100 percent of the sled’s weight on the pan.
- Kill Switch and Hook -The kill switch is always hooked first, allowing the sled operator to stop the engine of the attached vehicle in the event of an emergency or if the vehicle breaks free of the sled. The hook is used to connect the sled to the pulling vehicle and extends the weight of the sled to the vehicle’s hitch.
- Sled Operator – The driver of the sled. Has the responsibility of maintaining a controlled pull at all times. May pull kill switch if they feel something is out of control.