It’s What’s Inside That Counts- Part 2 of Jason Scherer’s Innovative New ULTRA4 Car

• May 12, 2014
• Story By
  Harry Wagner

The perfect King of the Hammers car would blast across the desert like a Trophy Truck and crawl through the rocks with the stability and visibility of a moon buggy.  Of course these attributes are at opposite ends of the off-road spectrum, forcing Ultra4 drivers and builders to determine their priorities.  Similarly, packaging for the perfect buggy would have all of the components tucked away safe from harm with a smooth undercarriage, yet easy to access in the pits and service between races.  And once again, compromises have to be made. Jason Scherer and his friends took all of this into consideration before the first tube was notched for his innovative new IFS Ultra4 car.  Each component was carefully considered with regards to myriad factors including weight, strength, ease of maintenance, and ground clearance.  The chassis on Jason’s new car, christened “The Gavel”, is 60-inches wide, despite only holding a single Beard seat.  This is far wider than the traditional rockcrawling buggies that Ultra4 cars have evolved from. “As speeds increase, so does the need for safety,” Jason explains. “I love racing, but at the end of the day I want to go home to my wife and kids.  This is one area where I was willing to sacrifice some weight for an increase in safety.” The wider chassis also allows for the radiator and various coolers for the Pacific Fabrication LS engine, and Reid Super Hydra 400 transmission, and hydraulic steering to sit next to Jason.  This lowers the center of gravity and keeps everything below the belt line of the car.  “Everyone wondered how I was able to do 130 mph in my old Jeep buggy that I won KOH in,” Jason shares.  “The radiator was in the front of that buggy, but now the norm is to package these components up high behind the occupants.  This creates a lot of drag at triple digit speeds though, since these vehicles don’t have windshields.  It acts like a big parachute, limiting top speed and decreasing stability.” The wider chassis also allowed for improved suspension geometry when compared to Jason’s past race cars.  The triangulated links locate a Spidertrax Pro Series Spider9 axle and hub package is used with a 10-inch ring gear and ARB Air Locker. Up front the suspension tapers in to maximize the length of the a-arms.  As with his previous car, Jason worked with Dallas Lund at Wild West Off-Road on the front arms and uprights/spindles.  “Dallas and I have both learned volumes from my last buggy,” Jason confesses.  “This time we made the arms to maximize ground clearance and take advantage of all of the travel of the RCV Series 30 CVs.” The front suspension geometry allows for over 40 degrees of steering, which is a huge increase from Jason’s last race car, making it more nimble in the rocks. The steering currently uses a traditional bump steer bracket attached to the steering rack, but the bulkhead of The Gavel was designed to allow Jason to run a “swing set” steering system for short course events. This steering configuration allows the inside tire to travel in the naturally shorter distance around the inside of a corner.  Properly engineered Ackerman allows the car to enter and exit corners at higher speeds with the entire contact patch of the Nitto’s on the ground. Even details like the wheel backspacing were not overlooked.  “My last car ran really deep backspacing, like Pro-4 racers do,” Jason explains.  “This makes for less scrub and allows the tires to rotate on the center of the king pin (KPI).  We are actually going to run less backspacing on our Method wheels this time though.” This is counter intuitive, as it causes the tire to swing while it turns, but that is actually the intended outcome in the rocks, as it gives the Trail Grapplers more opportunities to grab traction and propel the car forward.  “It was really tough when a finger sized outcropping could hang your diff and the car wouldn’t hunt for traction when you turned the wheel, since they pivoted so perfectly and had no scrub.”  The other deciding factor was finding a larger brake package than previously used in the rock crawling world.  A 10:1 Jamar dual master cylinder and peddle assembly feed massive six piston calipers that require a lot of real estate inside the wheel.  “Brakes are my best friend while racing and I use them to do just about everything from corner entry to setting up the car in the air,” Jason noted. Since the rulebook is wide open and the sport is still in its infancy, innovators like Jason Scherer see building a new car as an opportunity instead of a dilemma. Now that the chassis is laid out, the car is at Fishmouth Fabworks getting all of the mounts, triangulated tubes, and detail work fit and welded by the talented Dan Trout.  Don’t expect anything ordinary.  See more details below in the gallery and check back next week as we look further into the details as The Gavel starts to take shape!

Click here to read Part 3 of Jason Scherer's build!