SCORE Journal - The Official Publication of SCORE Off-Road Racing
Issue link: https://read.uberflip.com/i/1546251
BUILT LIGHT, BUILT STRONG Carbon Fiber in Off-Road Racing By Micah Anderson From Trophy Truck body panels and protective guards to racing seats and helmets, carbon fiber composite products have become a staple of modern motorsports. But what exactly is the secret sauce of carbon fiber? How are the components made, and why has carbon fiber become the material of choice for off-road racers chasing every possible advantage? For both racers and fabricators, carbon fiber is no longer simply the expensive lightweight alternative to fiberglass or aluminum. Manufacturers of specialized off-road racing and motorsports products are mixing fibers, changing layups, controlling stiffness, adding reinforcement only where needed, and building functional features directly into their parts. A lightweight hood and a life-saving helmet may both be made with carbon-weave fabrics, but they have almost nothing in common when it comes to what they are asked to survive. UNDERNEATH THE WEAVE IS WHAT COUNTS From a technical standpoint, carbon fiber materials get interesting when manufacturers stop treating it as a material substitution and start designing the part around exactly what it needs to do. That is the approach Danny Ebberts takes at EBBCO Offroad. His catalog ranges from body panels and aerodynamic components to structural storage items, shock guards, antenna guards, steering wheels, and even fuel-cell containers. Different parts, different jobs, and different requirements once they are exposed to heat, impacts, vibration, and hundreds of miles of punishment. EBBCO primarily uses prepreg carbon fiber, where the reinforcement already contains a carefully controlled amount of resin. The material is then stored frozen at 0 degrees F, thawed when needed, cut to specific patterns, laid into the mold, vacuum bagged, and oven cured at controlled temperatures. “Process and precision are everything in composites,” Ebberts said. Small changes in fiber orientation, resin content, vacuum quality, or the cure process can change how the finished part performs. EBBCO uses CNC cutting and machining for repeatable patterns and molds, along with multiple quality checks and nondestructive testing on certain structural components. That same level of planning starts before manufacturing ever begins. FiberwerX founder Jason McNeil looks at the loads a panel will be subjected to before deciding how it should be built. “We look at the shape, mounting points, impact zones, heat exposure, expected loads, and the amount of flexibility or stiffness the part needs,” McNeil said. For many FiberwerX race bodies, that leads to vacuum-assisted resin infusion. Dry carbon materials and reinforcements are positioned in the mold, vacuum-bagged and compacted before resin is drawn evenly through the laminate. The process allows FiberwerX to closely control fiber-to-resin ratio, compaction, and finished thickness. Just as important, manufacturers don’t have to make the entire part the same way. Additional layers or reinforcement can be concentrated around mounts, hinges, edges, and impact areas while other sections stay lighter. Material types, weaves, and fiber direction can change. Core materials can be added. Carbon sheets can be combined with Kevlar layers or other reinforcements when the application calls for different requirements. That ability to tune the construction is one of carbon fiber’s biggest advantages in a race vehicle. The material is only the starting point. What ultimately matters are how the part is designed, laid up, cured, and reinforced for the job waiting for it in the desert. A HOOD AND A SKID PLATE LIVE VERY DIFFERENT LIVES Trophy Trucks, Spec trucks and UTVs increasingly wear carbon body panels front-to-back. The weight savings are easy enough to understand, especially when weight is being removed high from the vehicle’s center-of-gravity. But bodywork is only the start. FiberwerX and EBBCO are also using composites behind the cosmetic body attire as shields and guards. Additionally, a race car might be fitted with carbon panels where aluminum was likely used just a few years ago, including inside the cockpit, for firewall protection, interior panels, and underneath the vehicle for skid plates, guards, and fuel-cell protection. Those parts cannot all be built the same way. A hood may need to remain stiff at speed, survive vibration and brush, and stay attached around hinges and latches. McNeil will design open sections to keep them relatively light while adding material around the concentrated-load areas. Move underneath the vehicle, and the priorities change quickly. FiberwerX also manufactures composite outer fuel-cell containers. These surround the actual fuel bladder and related components. The structure layup and laminate are substantially heavier than exterior bodywork, with additional reinforcement on the bottom, forward face, corners, and mounting areas. A panel protecting a fuel cell is subject to an endless barrage of rocks, gravel and debris being blasted on end. Carbon is stiff and strong, but McNeil is quick to point out that it is not indestructible. Hard, sustained and concentrated strikes can crack or delaminate the constructed materials. That is where Kevlar and other aramid reinforcements come into play. Carbon can provide lightweight stiffness and strength while Kevlar adds toughness, abrasion resistance, and resistance to tearing or puncture. FiberwerX uses hybrid construction around fuel cells, skid areas, and other panels where it matters most. “The strongest solution is often not an all-carbon laminate,” McNeil said. “It is the correct combination of carbon, Kevlar, fiberglass, core, resin, and local reinforcement.” A carbon hood and a carbon fuel-cell skid may share the same general material family, but their recipes can be completely different. CARBON FIBER AS ARMOR EBBCO produces over one hundred products, many of which are tools or problem-solving accessory items. Antenna guards and shock guards were among the company’s earliest products, and the same thinking has expanded into Starlink mounts and other specialized pieces. In these applications, carbon fiber’s high-strength and low-weight properties make it possible to add useful protection while providing convenient low-profile, aerodynamic-efficient advancements. The shocks, radio antenna, or piece of communications hardware may survive hundreds of miles without a problem until one rock lands in exactly the wrong place. As EBBCO founder Danny Ebberts puts it, “You can’t win if you don’t finish.” That is a pretty practical way to look at carbon fiber in desert racing. Weight still matters, but there are other implications to think about. A lightweight guard can protect a critical component while reducing the aerodynamic profile, which is another design consideration made before the product was ever put into production. The value is not always found on the scale alone. Sometimes it is measured by miles per hour and what is still working when the vehicle reaches the finish. Ebberts was also quick to point out the important considerations of building composite components with fire safety in mind. Carbon fiber itself is only part of that equation. The resin system and curing process can have a major influence on how a finished composite responds when temperatures and direct heat intensify. “When properly made and cured, composite parts have minimal fire hazards,” Ebberts said. “Raw carbon fiber is cauterized and pre-burnt, so it is just the resin that can be flammable. Our high-temp resin will have an ignition point of 1,400 degrees F and will not continue to burn without that extended high temperature.” According to EBBCO, the difference between resin systems and manufacturing processes can be substantial. He said some wet-layup or resin-infused parts using room-temperature-cure resins may have ignition points in the 250- to 300-degree F range. By comparison, he noted that aluminum, which carbon fiber frequently replaces in some of these applications, melts at roughly 600 degrees F. That makes heat exposure another part of the design conversation. A panel living near exhaust heat, a firewall, or other high-temperature areas cannot simply be treated the same as a guard mounted out in clean air. That is where carbon fiber starts functioning less like lightweight trim and more like armor — not because the material is invincible, but because the construction can be tailored around exactly what needs protecting. CARBON SEATS CONNECT THE DRIVER TO THE VEHICLE Spending long hours strapped into an off-road race vehicle is a physically demanding marathon. Through whoops, compressions, hard landings and constant direction changes, the seat has to control driver movement while managing chassis loads, restraint geometry and crash forces. Racetech President David Black says that is just the start of it. “We design seats around the forces drivers experience in extreme racing environments and during an impact,” Black said. “A rigid seat keeps the driver connected to the chassis instead of allowing the body to move independently.” Composite construction gives manufacturers more control over how that shell behaves. Racetech uses carbon and carbon-Kevlar construction with strategically placed energy-absorbing foams, allowing stiffness and support to be tuned throughout the seat. SPARCO USA Director of Sales and Marketing Alan Viado describes a similar advantage. Carbon fiber allows SPARCO engineers to control fiber direction, ply count, and carbon weave so different areas of the seat can react or control differently under load. Sections requiring greater stiffness can receive additional reinforcement, while other areas can be designed with more compliance for crash-energy management. There is a weight benefit as well. Racetech says its carbon and carbon-Kevlar 119 Series seats can save more than 7 pounds compared with an equivalent fiberglass model. SPARCO estimates its carbon seats can save roughly 50% to 70% compared with a comparable steel-frame seat. But both manufacturers make the same larger point: Weight is only one part of what a carbon seat brings to the race car. FIT, COMFORT AND FEATURES MATTER The best composite shell does little good if the driver does not fit properly inside it. “A comfortable driver will be able to perform at a higher level for much longer,” Viado said. SPARCO offers multiple sizes and widths because driver height, shoulder position, hip clearance and harness-slot location all affect fit. The company also developed an off-road cushion using closed-cell memory foam tuned to add comfort without allowing excessive body movement. Racetech follows the same philosophy with standard, tall, wide and wide-tall seat configurations, along with removable base and back cushions, low-base options and additional thigh-support cushions. Its squared-shoulder design profile provides full containment around the upper body and works with the harnesses to help control driver movement during cornering and impacts. Racetech also offers two seat features with clear desert-racing benefits. Its back-mount structure allows the seat to be supported near shoulder level and tied into the roll cage, which Racetech says improves structural load paths, driver support and chassis feedback. Integrated cool-air ducting is also available on its 119 and 129 Series seats. Air is routed through the rear of the shell and vented through the back cushion toward the driver’s lower back — a feature that becomes easy to appreciate during a sweltering hot Baja 500 race while wearing layers of fire protection and sitting beside a roasting drivetrain and exhaust heat. SPARCO approaches the same performance equation through fit, cushion tuning and shell construction. Its QRT seats are offered in carbon and Kevlar variants and also offer its QRT fiberglass seats as a lower-cost composite alternative that still meets applicable FIA standards. Whether the choice is carbon, carbon-Kevlar or fiberglass, both companies come back to the same basic requirement: The seat has to fit the driver, support the restraints and keep the racer properly positioned from the start line to the finish. Both companies are examples of what composites increasingly allow manufacturers to do: Tune the product construction to meet the demand and integrate competitive and unique features directly into their seats. A FEW OUNCES GET HEAVY IN BAJA The helmet may be where the benefits of carbon fiber and weight savings become easiest for a racer to physically appreciate. A few ounces do not sound like much sitting on a workbench. Put them on top of your own head and hit a few hundred miles of whoops and the equation changes. “Every time the vehicle crosses a whoop, drops into a compression, flat lands from a jump, hits a rock or bounces off a drainage rut, the driver’s neck and shoulders must stabilize the combined mass of the head and helmet,” explained Matt Winter, Marketing Director for Racing and Safety at Holley Performance Brands, which includes Stilo and Simpson. The co-driver gets the same treatment while bouncing between the course, GPS, gauges and notes. “In a desert race, a few ounces are not carried once,” said Kevin Albino, Holley’s Director of Product Management for Safety and Racing. “They are accelerated and stabilized thousands of times.” Balance matters too. A helmet that carries too much mass forward or backward can continually pull against the driver. A well-balanced helmet stays more neutral and requires less work from the neck. Carbon helps manufacturers optimize that mass, but Holley’s experts are careful not to turn the discussion into “carbon equals safer.” A helmet works as a system. During a helmet impact, the hard shell spreads a concentrated load across a larger area. Behind the hard shell is the EPS liner underneath. This is a specially designed energy-management liner, typically made from expanded polystyrene that compresses and manages energy while giving the head more time and distance to slow down. And then there are the padding and inserts that hold the head to the helmet, which is contingent on a properly sized shell that fits the end-user. “A carbon shell does not work independently,” said Luis Ortiz, Engineering Director for Safety and Racing at Holley Performance Brands. “The shell spreads the load, the liner manages the energy, and the fit keeps the system where it belongs.” Modern helmets may also use different liner densities in different areas to deal with different impact conditions. Additionally, premium helmets may offer more shell sizes to more closely match the driver’s head size instead of using one large shell with additional padding. That can reduce unnecessary bulk and weight. The biggest advances in carbon-fiber helmets have not come from one breakthrough material. Much of the progress has come from manufacturers gaining tighter control over how the entire helmet is designed and built. Stilo and Simpson use digital modeling to allow engineers to refine shell shapes and material placement before tooling begins. More precise cutting improves consistency from one carbon pattern to the next, while better prepreg materials and resin systems give manufacturers greater control over weight, stiffness, and structural performance. Stilo starts with prepreg carbon fiber cut into individual patterns. Those pieces are laid into the helmet mold by hand following a detailed layup schedule, which they refer to as a ply book. It tells the technician where every piece goes, which direction the fibers should run, where layers overlap, and where additional reinforcement is required. Instead of simply adding more carbon, manufacturers can now reinforce specific areas of the shell and remove unnecessary material elsewhere. The crown, chin bar, eye port, lower edge and restraint-anchor areas all have different jobs and experience different loads. Each can receive its own combination of material, fiber orientation and reinforcement. Stilo takes that philosophy another step with its Puro Technology, which carefully optimizes the use of fillers, clearcoats and lacquers applied to the exterior. That matters because every ounce counts — and not all helmet weight comes from the carbon shell. For an off-road racer, the rest of the helmet matters too. Field of view, communications, forced air, hydration, visors, visor sealing, head-and-neck restraint device mounting, hardware, padding, and other components all become part of the package once the driver is strapped in. Stilo’s Venti WRX helmet family, introduced in 2024, increased field of view by a reported 34% while retaining full-face coverage and offering configurations for sealed-visors or goggles. Holley’s advice for buying a helmet reflects that bigger picture: Start with the required certification, get the fit right, make sure it works with the vehicle and other safety gear, then worry about weight. FROM THE RETAIL COUNTER TO THE UTV MARKET Rugged Radios gets to watch another part of the carbon-fiber cycle play out every day: what racers are actually willing to spend money on. Director of Marketing Dustin Ensign confirms helmets are where Rugged sees customers invest. “Racers spend hours wearing them, so taking weight off your head and neck isn’t just a spec on paper,” Ensign said. “It’s something you notice every time you put on the helmet and even more so by the end of a long day in the racecar.” Rugged is also seeing carbon show up in recreational communications equipment, including lightweight carbon-fiber headsets often used in pre-running. “Like a lot of technology in the off-road industry, it starts in racing, then works its way into recreational products,” Ensign said. FiberwerX also sees a boosted interest in its carbon fiber products from recreational and street truck customers. “We have always offered carbon fiber upgrades to any of our truck fender panels, but the UTV market is on another level,” McNeil shared. UTV racing has become a major growth area for carbon bodywork and protection. Not long ago, FiberwerX developed carbon body packages for the Polaris RZR Factory Racing program, and that really took off. Now the FiberwerX UTV catalog offers full carbon body kits including carbon hoods, roofs, doors, and bedsides, for certain UTV applications. For the dedicated UTV racers, McNeil says we can dress them up with ev en more for dedicated weight savings, including firewalls, interior panels, and fuel-cell protection. A UTV racer working with considerably less horsepower than an unlimited truck will notice even the slightest incremental performance gained by dropping weight out of the vehicle. SMARTER CARBON AND SMARTER ENGINEERING The future of carbon fiber in off-road racing probably does not involve covering every surface of a race vehicle in more or less layers. The people making these parts seem more interested in using it smarter. Thoughtful design, first modeling, and forward engineering. Better 3D scanning, refined processes, advanced materials, optimized tooling, CNC material cutting, and of course, quality and control are making all of that easier to innovate and repeat. And that may be the real secret sauce. Carbon fiber is not one material doing one job, but it is a marvelous and extremely versatile black weave we can appreciate. SJ