SCORE Journal - The Official Publication of SCORE Off-Road Racing
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AWD Trophy Trucks; Past, Present, and Future By Stuart Bourdon Photography: Get Some Photo, Stuart Bourdon, Geiser Brothers, and Mason Motorsports SCORE Trophy Trucks are the heavyweight boxers of off-road racing and the pinnacle of the SCORE World Desert Championship competition. It’s the premier class to which almost all drivers who want to compete against the best and fastest aspire. In the last few years, the headlines of many stories about off-road racing have been about the “new” four-wheel-drive, now called All-Wheel-Drive (AWD), Trophy Trucks. While there have been four-wheel drive vehicles in SCORE from years past, the interest in these vehicles was re-ignited when new technology became available and AWD Trophy Trucks began winning with some regularity in 2016. Justin Matney beat the field driving a Geiser-built AWD Trophy Truck on February 6, 2016, at the Parker 425. While it may be the new trend in Trophy Trucks, AWD is not new in desert racing. An Early Start The first AWD vehicle to win a major off-road race was a Bill Stroppe-built Ford Bronco, driven by Rod Hall at the 1969 NORRA Mexican 1000. Rod won the race overall, beating the motorcycles by nearly 10 minutes. You could think of the Stroppe Bronco as an early “Trophy Truck” as it was built on a tube chassis, featuring a primitive fuel cell, a completely reworked interior with racing seats and harnesses, custom roll cage, and custom dashboard stuffed with multiple aftermarket gauges. In the 1990s the MacPherson racing team successfully fielded a four-wheel-drive truck. MacPherson had been working with the GM engineering team, acting as a test program that would eventually lead to the development of the modern electronic four-wheel-drive systems found today in many GM trucks and SUVs. An early Herbst truck campaigning some 20 years ago featured a four-wheel-drive system with an electric clutch to slow the front wheels when the speed sensors saw that the front and rear driveshafts were spinning at close to the same speeds and engaged the clutch when they weren’t. There were others, and some of those early attempts had limited success, mostly due to mechanical issues such as the CV joints that couldn’t take the extreme angles. Limited wheel travel upfront compared to the two-wheel-drive trucks was a handicap and acute linkage angles created steering issues when the suspensions were at full compression or rebound. That early Herbst AWD truck had about 16 inches of overall travel. Today’s AWD Trophy Trucks are running up to 24 inches of wheel travel and motivated by engines with more power than ever, which has leveled the playing field and made them very competitive and a winning formula in the SCORE Trophy Truck class. The New Wave We talked to Rick Geiser of Geiser Brothers about that first Justin Matney truck and the development process it went through. “When we built our first AWD Trophy Truck we rushed a little bit to get there, but we did about 800 miles of testing, and at that point we felt we were ready to race it. We went to Parker in early 2016 and it won that race overall. We built that truck for Justin at RPM Racing. He’s a good driver and Justin’s very easy on equipment. He ended up qualifying in one of the top positions and then went on to win the race overall. We came back home and were pretty excited but then spent a lot of time improving it.” “That’s when we started having all of our, let’s call it teething problems. We would fix one thing and another thing would break. We redid the transfer case and then the front diff broke. We beefed up the front diff and the transfer case broke, and we went back and forth. That process sort of screwed us up for a little while. We finally got the truck to a point where it was reliable and won four races overall. Now we are in the process of building a brand-new truck for Justin and we’re talking about an AWD truck that will be the next step in technology.” Rick added, “We expect to have it ready to race for the 2021 SCORE season.” Geiser also built a one-off twin-engine AWD truck for Clyde Stacy,” Rick said, “The front engine and transmission drives the rear axle and the rear engine and transmission drives the front axle. We had quite a few problems with it at first, but now it runs two LS motors, works great. He won the 2017 and 2019 SCORE Trophy Truck Legends Class Championships with it.” Mason Motorsports has also made some big steps forward in the development of AWD Trophy Trucks. Neal Mason, the engineer, designer, and builder of the Mason AWD Trophy Truck told us, “Rather than start with a two-wheel-drive truck chassis and turn it into an all-wheel-drive we started with a blank sheet of paper. We decided that using portal uprights in the front to offset CV angles and reduce the loads in the CV joints and axles would give us the same kind of wheel travel and ground clearance that two-wheel-drive trucks. We ended up designing a mid-engine engine truck and started by partnering with a company called Xtrac for the transfer case and front differential and adapted them to work in our truck.” Neal continued, “Some of the initial struggles we had with the transfer case and front diff motivated us to design our own integrated front differential/transfer case in-house that was specifically made the AWD Trophy Truck. Our front diffs and transfer cases are a combined unit, we did all the engineering and design work here. We manufacture the case and then use Xtrac to manufacture the gears. They have the manufacturing capability to cut custom gears that we design.” “We also decided to design and build a transmission from the ground up.” Neal explained, “The built Turbo 400s typically used in Trophy Trucks weren’t up to the task. We wanted more gear ratios to optimize the acceleration that you’re able to get with the AWD. Our transmission is a 5-speed and has individual spur gears and they can be easily changed so you can fine-tune ratios. It doesn’t use planetary gears and instead of dog rings and mechanical stuff with ignition cuts to shift it we apply each gear with a hydraulic clutch like an automatic transmission so there are full-power shifts that don’t interrupt acceleration.” Ron Weddle at Weddle Industries knows a lot about the types of transmissions and transfer cases used in buggies. They also developed AWD units that can be used in a Trophy Truck. “The ST6 six-speed transmission comes in two versions for an AWD truck application, one for a front engine package and one for a rear engine package,” said Weddle. “It utilizes a pneumatically controlled wet clutch assembly to drive the front wheels and absorb torque spikes in the driveline. Its torque limit (where it will briefly slip) can be adjusted and be switched on and off while on the fly depending on the conditions and various inputs. We also offer a very strong and compact front differential (Albins AFD-100). The ST6 has been used successfully in some short course trucks, including the one RJ Anderson drove to the 2018 Lucas Oil Pro4 series championship. This year (2020), if we get to go racing again, these products will be seen for the first time in the Trophy Truck desert racing class.” Robbie Pierce at Jimco is best known for building superb off-road racecars and is building an AWD Trophy Truck for a customer. “We plan on debuting it at the 2020 SCORE Baja 1000,” Robbie said, “I have to hand it to Mason, they’ve done a really good job building them, but we will have our take on how to package one, and hopefully, it’ll be a little better. It’s kind of what we do, and we’ll see what happens at 1000.” Robby Gordon recently did some testing (including a qualifying run at the Parker 425) in his two-wheel-drive Trophy Truck that he converted to AWD, but rumors have been circulating in the off-road scene that Robby was building a new AWD Trophy Truck. When asked about it during our recent interview for the upcoming debut of his all-new Speed UTV (check out the feature on the new Speed UTV in the March 2020 SCORE Journal), he replied, “I am building a new truck and it will be at the next SCORE Baja 1000, but I’m not building it to sell, I’m building it to win.” It’s our humble opinion Gordon’s AWD Unicorn (seen testing in the Speed UTV YouTube video below) may be based on the proposed Speed UTV “truck” model and its front drivetrain box design. The Good, the Bad, and the Ugly What’s the big deal with AWD Trophy Trucks? We talked to some drivers and builders to get their thoughts. Justin Matney, who shook up the sport with his first overall win in 2016 and then went on to more firsts and successive high-placing finishes, put it simply. “The AWD Mason Trophy Truck puts more power to the ground, has less tire spin, and much better speed and traction through the corners.” Bryce Menzies has been scoring big in off-road racing for more than a decade and racked up major wins in two-wheel drive and AWD. “The AWD Trophy Truck pulls you through every corner and over every bump. To constantly be moving forward and eliminating tire slip is a game-changer. I have two AWD Trophy Trucks (Bryce has previously said that allows him to race more events due to the lengthy pre-race prep-time turn-around of the new trucks), one built by Huseman Brothers, the other built by Mason Motorsports. Both have similar bodies built on the Ford Raptor platform. The Huseman truck has the motor in front like most two-wheel-drives, the Mason truck is a mid-engine. Both run an Xtrac transmission and use paddle shifters. I wanted the cockpits to be extremely similar so it would be a smooth transition driving both trucks back to back. The Mason has front portals, the Huseman runs a different front diff made by Xtrac.” Builder and driver Rick Geiser framed his feelings this way, “With two-wheel drive, you can drive twice as hard and still make it to the finish line, where an AWD has many more moving parts and they can still be a little bit fragile.” When asked about the pros and cons of the AWD Trophy Truck, Neal Mason explained, “Anytime the vehicle has to slow down and speed back up rapidly, the AWD system offers an advantage, and anytime you are accelerating AWD is an advantage. It shines in corners, helping the driver keep a tighter line through and accelerate out of a corner quicker. It helps maintain better lateral traction as well as greater acceleration traction.” Andy McMillin now has a couple of races and lots of testing and pre-running under his belt in his Mason AWD Trophy Truck. Andy told us, “I think the biggest thing to get used to is the speed difference coming into a corner. You’re going quite a bit faster. There’s a lot less wheel slip and it’s more hooked up. Because there are not many AWD trucks out there yet, we’re sort of the Guinea Pigs right now on how long parts can last before replacing them. It’s sort of like being in a Beta test at this point.” Christian Sourapas and his brother Brett took delivery of their AWD Trophy Truck last year, and Christian spoke to us about their experiences with it so far. “The portal hubs and front suspension geometry that Mason has designed allowed us to have an AWD truck that can do anything a two-wheel-drive truck can do. We’ve had our struggles though. We blew the front diff one race, and right now our little gremlin has been keeping rear gears alive. We’ve lost two rear gears in a row and that’s been frustrating. It has a lot more power than my two-wheel-drive did. The more power, the more problems.” Cameron Steele has been driving fast cars and trucks off-road for many years and covered about 500 miles pre-running in an AWD Mason truck that’s the twin-sister truck to the one recently piloted by Ricky Johnson. Cameron told us, “AWD gives you the ability to maintain traction and build a lot more speed quickly so you can accelerate out of the corners faster than in the two-wheel-drive trucks. And when it comes to soft (silt and sand) sections of the course, AWD has a huge advantage over two-wheel-drive.” SCORE Trophy Truck Class Split? How the influx of all-wheel-drive trucks affects the competitiveness of the Trophy Truck class is a subject of much speculation. Will AWD eventually dominate the class or force a split in the Trophy Truck class? Here’s what the builders and drivers we talked to think. Rick Geiser said, “From a builder and a racer’s point of view, the Trophy Truck class is supposed to be unlimited, a ‘run-what-you-brung’ sort of deal. I believe that AWD has huge advantages, but I don’t believe it’s a complete game-changer.” Neal Mason told us, “A lot of people are already talking about splitting the class into two groups, two-wheel-drive and AWD. However, I think most drivers, builders, and sponsors are in the unlimited SCORE Trophy Truck class because it’s the premier class in off-road racing. If the people racing two-wheel-drive are split into their own class, it may feel like not being in the top-tier class anymore. The two-wheel-drive Trophy Trucks are still winning races, and with a good driver, they will always have a good chance of winning.” Bryce Menzies said, “I don’t think it will make two-wheel-drive obsolete but it’s the start of something really good. We’re developing a lot of new parts for these AWD trucks and a few other teams are also working hard to improve their trucks. The test will be getting these parts to last and be strong enough to make it through a Baja 1000 race, but I do see an AWD Trophy Truck winning in Baja and it’s definitely what I will be driving in the future.” When asked about a SCORE Trophy Truck class split, Andy McMillin said, “I don’t think splitting the class is the right thing to do, certainly not at this point. Making more classes is not in the best interest of the growth of our sport. There are already so many classes that for the spectator it can be confusing, and if we’re trying to reach new fans that don’t know about our sport, it’s not a good idea. What’s Next Neal Mason talked about what he thinks is likely the next big step in Trophy Truck technology. “It’s coming down to more electronic control of things going on in the trucks. Like being able to dial in live suspension tuning, and possibly live interactive differentials. It’s going to be more things that can be tuned and controlled to do exactly what you want. I think we’re looking at more electronics to actively help you drive the race truck better.” SJ