Off Road

That sounds like quite a ride. When you consider that his Pro 4 truck is a custom-built Toyota Tundra powered by an 800hp iForce V8, it makes sense that it's a trip to be enjoyed.

The Pro 4 class, as CORR calls it, is the fastest class in short-course off road racing. Unlike desert racing, short-course racing involves many laps around a course that's typically one- to two-miles long. Another difference from desert racing is that everybody starts at the same time, and it's a race against the other drivers, not the clock.

The specialized type of racing calls for specialized equipment. Greaves builds his trucks from the ground up - "It's a complete tubular chassis. We start on a plate and set the driver on one spot, the engine on another, the rear end here and the front drive there, and start attaching A to B to C." In fact, Greaves builds many of the trucks that are racing in CORR and other series.

What differentiates the trucks from one OEM manufacturer to another is the body and engine. In this case, Greaves stays close to the original Tundra template as much as possible. "It's widened a bit, and flared a bit, but the roof lines, the body style are real Tundra. It even uses a production grill," he explains. "The fans can really relate to it: 'This looks like my truck, it's just a little more badass.' Then they see the motor and you explain that it's the Tundra block and it has the Tundra heads, so they love that, too."

The engine that powers Greaves's Pro 4 truck is relatively small - in CORR terms, anyway - at 337 cubic inches, and the rules for that particular engine require 11.5 lbs. per cubic inch, putting the truck at almost 4000 lbs. "So our main goal is to be as light as possible and to get down to that weight limit," he says. "But you've got to be sure that it's light in the right spots, because the next most important thing is, it's gotta be able to go to war. You can have the fastest truck on the track, but you're not going to win unless you can go to war with that truck. You're going to be doing a little bit of bumping and banging."

Which comes full circle to the special requirements for a short-course off road truck. In addition to needing to be ready for contact with other trucks, there are some other differences as well. A short-course truck is also facing very different terrain to the guys out on Baja, for example. For that reason, it only needs about 20 in. of suspension travel, where a SCORE Trophy Truck typically has 30 or more. (A stock Toyota Tundra has less than half the suspension travel of a Pro 4 truck.) Although it has 20 in. of suspension travel, the Pro 4 truck sits only about 10 in. off the ground.

"If the average guy jumps in my truck and takes it for a ride, he's going to say, 'Man, it's stiff. I can't believe you're able to drive it like that.' Then, if you get it up to speed, where it's designed to work right, all of a sudden it's a pleasure to drive," Greaves explains. "It's a very aggressive setup, made to go wide open, a tad bit out of control. It's designed to recover - it's designed to stick whichever way it lands. If it lands 90 degrees to the track, it needs to stick and you need to be able to gather it up and keep going. You have to design it with the thought that anything can happen out there. It has to be able to land on its nose and keep going forward.

"It's very aggressive. A desert truck is a marshmallow against this truck," he continues. "But then these things won't really go through the desert, because you have to have big wheel travel. This thing would skip across the stuff, not go down into the holes."

A Pro 4 truck, he notes, is what happens when there are very few rules. While there are wheelbase and engine location parameters, it's very open. "You put parts where you want them, because you want them there," he says.

It's a high-tech solution to a very specific problem - getting around tight turns, over jumps and across the whoops as quickly as possible. It all comes together in race wins and championships when the truck has a driver with the same, singular purpose. And as the record shows, Johnny Greaves is exactly that driver.