01/29/2025
We are proud to show you Jason Washburn’s 4900 class racecar and Wide Open Design’s entry into the Side by Side full tube chassis market. We’ve been working on this for over 5 years now, learning and improving with each build. Every year on the way home from King of the Hammers, Jason talks about building a racecar and 2025 he pulled the trigger. We couldn’t be any more excited to see him race King of the Hammers and to see him test out this prototype chassis in the toughest one day off road race in the world.
The first thing you notice about this buggy is its low stance. At 82” wide with a 107” wheelbase and a belly height of 18”, this buggy looks like it’s going fast even when it’s sitting still. The roll cage ties the car’s beltline together creating that aggressive look. The chassis is mainly built out of 1 ¾” tubing. At first glance, you may think this chassis was built for smaller riders however that couldn’t be further from the truth. We have had people over 6’ 2” sit in this chassis without issue. We accomplished this by mounting the seat to the bottom frame rail of the buggy. The control you feel sitting in the buggy is unreal. Even with sitting that low, you can see both front tires from the driver’s seat which furthers the confidence you feel in the buggy. As much as we wanted a chassis that performed well, we couldn’t forget about it being visually appealing. The front and rear of the car are considerably narrower than the cockpit which takes away that blocky feel. The intrusion bars are recessed allowing your light bar and chase light to be tucked away from damage and to keep a smooth look throughout the car. The tool box and the spare tire are angled down allowing your eyes to roll easily off the back of the car. All of these details come together to create a chassis that is as tough as it is good looking.
This buggy started as a 2022 Polaris RZR Turbo R. We took that machine, completely tore it down and 3D scanned a majority of the parts. This step was key in making sure the chassis designed in CAD would accept the OEM components we wanted to reuse. These parts include the engine, transmission, radiator, intercooler, fan, front differential, steering rack, knuckles, unit bearings, and brakes. One of the best things about this chassis is that it’s designed to use as many stock parts as possible. That means you can build this chassis on a budget or pick and choose from a huge selection of aftermarket parts to build the buggy that best suits your needs. With this being a racecar, the parts we decided to upgrade include A-arms and trailing arms, sway bar, axle shafts, tie rods, clutch components, shocks, springs, exhaust, seats, steering wheel, and a winch.
The Turbo R comes stock with 181 horsepower. We equipped this machine with an aftermarket exhaust system and a ECM tuner for some extra power. The factory radiator and fan do a fantastic job of keeping the engine cool. We moved the radiator to sit down right in front of the engine and behind the seats. Fragola components were used to plumb the car throughout the build. To manage the power and larger tires, Crash City SXS sent us their clutch kit which will give us more adjustability and belt life than the factory setup. Taking that a step further, we installed a temperature gauge in the clutch cover to monitor belt heat. From there, we partnered with RCV and installed a set of PRO series axle shafts to put up with the abuse of racing and hardcore riding. The RCV shafts spline directly into the factory unit bearings which was another reason we chose the Turbo R platform. Historically, wheel bearings have been an issue on various machines but the Turbo R’s unit bearings are known to be much stronger. We also installed a set of Super ATV tie rods. All of these components allow us to turn these 37” OBOR Rock Scraper sticky tires wrapped on a set of Raceline Alpha 15” Bead Lock wheels without stressing broken parts.
Another feature about the Turbo R platform is it’s long travel suspension. Whether you keep the stock arms or decide to upgrade them, you automatically start with over 22” of suspension travel front and rear. We worked with Radflo Shocks (not pictured) and are excited to be running a set of 3” Internal Bypass Shocks front and rear with two different clickers to control compression. These are the first set built for a Turbo R and they will bolt on to your factory machine. These shocks give us fantastic adjustability and great control whether we are bombing the desert or ripping through the rock trails. Wrapped around these massive shocks are a set of Eibach 3.75” Springs (not pictured). Eibach also hooked us up with their 3 position UTV sway bar. With the adjustability of this unit, we are really excited to be able to change the car’s handling for different applications. This buggy is running our Limit straps with a 3 position adjustable mount to keep the shock travel in check. To strengthen entire assembly, this buggy received Metalwerx A-arms and trailing arms, RCV pro series 300M ball joints, as well as NRP radius rods. Just looking at the car you can tell the massive strength upgrade these components have over the stock machine.
Jason wanted to run a single seat car for racing however he ultimately wanted a two seat car. This car features a ditch cover, allowing you to remove the passenger seat for racing, then switch it back to a two seat car for trail riding. We partnered with PRP to run their ALPHA composite seats, ratcheting safety harnesses with removable pads, window nets, and flat leather wrapped steering wheel with their direct install quick disconnect. The Alpha seat and harnesses allow you to drive hard without feeling sore after a day of riding or racing. The window nets provide a nice barrier from the race track, and the quick disconnect makes getting in and out of the buggy a breeze. Another standout interior feature is the dash. Combining CAD design and cardboard, we cut, broke, welded, and ground the dash to get it just how we wanted it. The stock gauge cluster was retained for simplicity. We built an IPad mount into the car that will navigate the driver while racing and can control music through his Rugged Radios communication system while trail riding. Underneath that is the display for the front and rear camera system. This gives the racecar fantastic visibility when navigating tough rock trails or simply backing out of camp. The rear firewall features the Wide Open Design logo which not only looks great, but is lined with stainless steel mesh that provides the proper air flow to the radiator. These details come together to create an interior that allows you to drive the car to its full potential.
Other details we worked into the buggy feature a Warn RC 9.0. This winch is rated for 9000LBS and will be able to quickly drag the 2500LBS buggy straight up thanks to its high line speed. We are also utilizing Warn’s wireless remote kit to control the winch from outside of the car. Custom splice sent us 100’ of 5/16” winch rope and Factor 55 got on board with a winch recovery kit. The trunk is designed to house the air filter and air box and we built in a cover to easily access the spark plugs. It holds the jack, houses spare belts, a tool bag, first aid kit, and factor 55 recovery gear and all of it is accessible by opening the hinged spare tire carrier which is attached to the lid of the tool box. To protect the bottom of the car, a mix of 3/8” and 1/4” 6061 aluminum was cut and is held in place by countersunk hardware to provide the buggy a smooth belly to slide over rocks. To give the buggy a finished look, Carbon fiber wrap was used which covers plenty of different components throughout the build. Paired with Graphic Effect’s wrap, the buggy had everyone in the shop saying “Now it’s a racecar”. Between the raw chassis and wrapped panels, this buggy looks ready for the start line.
We’re in the business of buggies and this chassis is no exception. We wanted a product that fits right in line with our other chassis and we couldn’t be more thrilled on how it turned out.
we are excited to see how it performs out in the desert. Check out our YouTube for frequent King of the Hammers updates, and when you see us on the lakebed be sure to say hello!
Off Road Parts and Fabrication in Murfreesboro, TN Wide Open Design is the off-road parts superstore. We carry parts from the industry's top brands for your rig.
