<%@LANGUAGE="VBSCRIPT"%> ROCKCRAWLER.com - XTV Raptor (Part II)

ROCKCRAWLER.com
XTV Raptor - Part II

By,
Dave "Rockwizard" Baker


Heart and Soul

Rear - FlexedFor the running gear, we would accept nothing less than the attributes offered by one ton components. We gave serious consideration to 2 1/2 ton military axles, which we will offer as an option to our customers, but for this light-weight application, we chose the strength and reliability of a Dana 60 front and a Corporate 14 bolt rear. We stuffed the differentials with 5.13 gears and Timken bearings from Randy's Ring and Pinion and full Detroit Lockers provided by TracTech, Incorporated. Even though we are running 44-inch tires, the weight of the XTV Raptor allows the axles to handle the larger tires.

We followed the same principle in choosing an engine. Although several engine options will exist for our customers, Mike and I decided on the venerable Vortec 4.3. With headers, this engine will produce approximately 230 horses and it's so light, that I can almost throw it around the shop by myself. Due to the Raptor's low gearing, this engine provides instant fuel injected throttle response and superb power throughout its gear range. We scavenged this Vortec 4.3 from a GMC Safari mini-van that was hit in the rear. I suggested to Mike that we should register the vehicle with a personalized tag that reads, "MINIVAN."

For the drivetrain, a Turbo Hydromatic 350 was outfitted with a rebuild kit, shift kit and Hurst Quarter Stick Shifter. This bolts via an Advance Adapter to a Klune Industries Klune-V "David" Planetary Crawler. From there, we are the test pilot for a new adapter from Klune Industries connecting their planetary crawler system to an NP205 manual version. This all equates to an approximate 131+ crawl ratio times the torque converter. The Klune-V planetary crawler is responsible for an additional 4.7 times the current gearing. It makes the extreme low range possible. Once again, this setup is plenty strong for the XTV Raptor. (Note: an Advance Adapters Atlas II would increase the low range considerably. Klune Industries Klune-V will bolt up directly.)

Claws

Dave cutting a tireWherever traction is needed, Interco is always there. Mike and I decided on 44x19.5x15 TSL Boggers for the rear. As soon as the tires were unloaded from the delivery truck, we started cutting out every other lug. Talk about some funny reactions from customers. For the front, we chose 44x18.5x15 TSL Swampers. We didn't cut these, but rather chose a reptilian pattern to groove. Although it looks pretty cool, the grooves make the tire much softer. With 2 lbs. of air pressure, you can press your knee into the tire and it will literally pinch through your jeans to the skin. Talk about traction!

Beadlocks for our application were a must-have. Beadlocks, however, are very expensive. We decided to make our own, utilizing black steel wheels and beadlock rings from Bart Wheels. None of our distributors offered 15x10 black wheels with an 8-lug pattern. They all offer these in white, but not black. Most wheel manufactures would gladly build us a set, for about the same amount as buying the beadlock wheels. Go figure! No problem, we ordered the white ones and Mike Trammell Paint and Body handled the rest. We dropped them off white and got them back black, sweet!

Agility and Stance

XTV Raptor Rear/SideThe agility to move swiftly through a boulder strewn trail, the ability to take a rock ledge with authority and drop off the same ledge and soak up the fall. We accomplished this with the use of Bilstein shocks, Firestone airbags and a proven suspension setup. For the front, we utilized Bilstein 9100 series coil-over shocks with 17 inches of travel. The Firestone double-convoluted airbags tuck directly in front of the mounting point between the chassis and the upper four-link brackets. The rear suspension is quarter elliptic, utilizing our custom-designed quarter elliptic spring mounts. The airbags are mounted atop the springs right in front of the brackets next to the chassis. Mounting the airbags in this manner allows for 7.3 inches of travel at the wheel for every 1-inch of travel at the airbag. Each bag is controlled separately via a three-way return-to-center toggle. This provides us our up, down and side-to-side equalization. The toggles we use are important because they are air-valved instead of electric oriented with solenoids. This means they are more expensive, but relatively simple and rebuildable.

Both front and rear suspension setups are held in place by an upside down four-link. Not "reversed" necessarily, the front is reversed but it's upside down as well. The front outer links are heavily armored to accommodate the incredible amount of force applied by the airbags. All other links are made of 1 1/4" OD 5/16" wall tubing and sleeved with 1 1/2" OD 1/8" wall tubing. This combination is not impervious to bending, but resists it quite well.

One of the things I despise most is trying to steer a vehicle straight and getting a bunch of guff! For the steering, Mike and I chose a dual hydraulic cylinder setup. We sell this setup as an XTV Hydrosteer System for most solid axle applications. As with the XTV Raptor, components consist of two 2500psi hydraulic cylinders, orbital, quick disconnect, 3 1/2" column, and steering wheel. It easily operates off of the existing power steering pump and allows one hand control. Aftermarket pumps are available from AGR.

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