Trophy Trucks and Pro2 Trucks are at the top when it comes to off-road racing. What makes them handle their type of racing so well?
When you think of Short Course Off Road Racing or Desert Racing, thoughts of high horsepower motors and tons of suspension travel come to mind. The 2 vehicles that dominate both of these types of racing are the Pro-2 in short course racing and the Trophy Truck in off road racing. And though these types of off road race trucks have similarities, because of their terrain, they are both very different. Let’s see how their “race course” determines their build.
Short course race tracks include tight turns, triples and doubles and huge table top jumps with generally no rocks or brush to contend with like in the desert. Now because of this type of race course a Pro-2 has to be quick, nimble, and as light as possible to make it easier to take the abuse they are put through. Try jumping your Ranger prerunner off a 40 ft table top and see what happens, well you better not, that could get ugly.
Racing in the desert creates its own set of challenges for racers. Huge boulders, brush, and lots of dust are what make up the course in a desert race. Trophy Trucks have to be able to not only contend with these types of obstacles but do it for hundreds of miles. Though it helps them to be nimble, durability is the main focus here.
We’ll start with the chassis design. Pro-2 chassis are limited to make racing even between competitors. Even the cage design has certain mandates on them to keep things even. Remember the key to short course racing is to make the truck handle like a rally car and be able to jump from unbelievable heights, so the idea is to keep the chassis sitting as low as possible and make it as wide as possible for stability. Here is where the rules come into play. Pro-2s must have a minimum ride height of 10 inches, with a max wheelbase of 117 inches and a track width no wider than 93 inches. Pro-2s also only need to carry one occupant, so they are able to move the engine backwards in the chassis to help create a 50/50 weight balance. The rules dictate that they must carry at least 45% of the weight up front.
Now with Trophy Trucks the chassis and cage design are open with a few rules placed on wheelbase and track width. The wheelbase on a Trophy Truck is usually between 125 – 130 inches and the track width is between 89 – 95 inches, so you see there is some flexibility here. Trophy Trucks usually have a driver and co-driver so engine set-back can not be as extreme. Most Trophy Truck builders shoot for a 60/40 weigh distribution. Trophy Trucks generally weigh in at a hefty 5000 to 6000 lbs, where a Pro-2 must be at least 3750 lbs. Contending with the desert terrain and the long distances travelled it is important for a Trophy Truck to not only carry two people, but large amounts of fuel (65 to 100 gallons, where a Pro-2 carries only 20 gallons) and spare parts, like 2 spare tires which all adds to its weight. A Trophy Truck must also carry some essential parts in the cockpit to allow the driver and co-driver to navigate the race course, GPS, Parker Pumpers for fresh air, a radio system to talk between themselves and their pits, all these items add weight.
Because of the weight differences and terrain, as well as the governing body of each type of racing the suspension designs are worlds apart. Trophy Trucks have no limits other than the laws of physics will allow. Long A-arms up front and huge trailing arms out back allow a Trophy Truck to achieve 24 – 28 inches of travel up front and an even bigger 28 – 30 inches in the rear.
Pro-2s on the other hand are limited to a “mere” 18” in front and 20” in the rear. Even the shocks used by each vehicle differ again because of the course and speeds they run at. Pro-2s usually can hit speeds of 50-55 mph on the course, where it is not uncommon for a Trophy Truck to hit speeds of over 120 mph. When travelling at those kinds of speeds you need a large shock that holds a ton of oil so it doesn’t fade with the heat that is generated by cycling the suspension for such a long time.
Pro-2s usually use a 2.0” coil-over in front and a 2.5” bypass shock in the rear. Now this is very general, we have seen some racers with different designs, but this is what most racers use. Trophy Trucks on the other hand must rely on multiple shocks at each corner and their size is almost double that used in a Pro-2. 3.0” coil-overs ride alongside 4.0” bypass shocks with huge reservoirs at each corner of the truck. Using the larger shocks helps handle the added weight and speeds that are possible by these trucks. So you can see how weight, terrain and speed all have a direct impact on the design of these two race vehicles.
We mentioned earlier that Pro-2s must be nimble and with the types of turns built into the tracks they must be able to get out of the hole quickly. This is done so by an 800-900 HP motor. Image a 3750 lb. truck with 900 HP on tap, it’s like holding a loaded gun. Now even though a Trophy Truck is almost twice as heavy as a Pro-2, they are still capable of blistering speeds. Most Trophy Trucks are powered by 700 – 800 HP motors that are a bit more mildly built than a Pro-2’s motor since a Trophy Truck has to run hundreds of miles in a race and a Pro-2 might run 8-10 miles on each heat.
Even something so simple as tire design makes these 2 race trucks different. Pro-2s usually start with a mud terrain tire then cut grooves of rubber out to aid in traction. Tire size is 35”. There is a lot of testing done on what types of groove patterns give the most amount of traction. Grooving a Pro-2’s tire also makes them lighter, this lessens the unsprung weight, which is another reason less shock is needed.. Trophy Trucks on the other hand use a desert specific tire, usually with multiple plies on the sidewalls to help protect against punctures and are 37” – 39” tall. The taller tire helps to make bumps and dips in the desert seem smaller, but also make the tire heavier.
As you can see, both of these trucks dominate their type of racing, yet because of the terrain they race on, their design is so different, yet equally impressive. If you have a chance to see either of these 2 types of vehicles up close you too can see how wildly different they truly are.
I would like to thank Baja Kits by Brenthel Industries with their help on the key points of these 2 trucks. Along with building unbelievable long travel suspension kits for prerunners, they also build Trophy Trucks and Class 1 buggies, so their help was invaluable.