XTM racing X-Terminator RTR

Radio Control Car Action, Jan 2003 by Gonzalez, George M

track test

1/8 SCALE NITRO

Big-Time Big-Block Buggy

XTM IS KNOWN FOR STARTER BOXES, big-block conversion kits and CNC aluminum accessories for the popular T-Maxx, but the company also makes 2WD and 4WD RTR 1/10-scale electric- (Baja Bullet) and nitro-powered (Baja Blade, Baja Outlaw) off-road trucks. It was XTM's .247 nitro engine, however, that put the company in the limelight and started the trend toward larger-displacement big-- block nitro engines. We knew that it was only a matter of time before XTM released a chassis that would be a worthy foundation for the potent 24-7 mill, but we didn't know that XTM had two vehicles in the works!

You can read the "First Drive" on XTM's new X-Factor monster truck elsewhere in this issue, but now it's time to focus our attention on the second stage of XTM's big-block assault: the X-Terminator. The X-Terminator is a ready-to-run, 1/8-scale 4WD buggy that's loaded with impressive features and many well-thought-out details, but its large engine makes it one of only a couple entries in the rapidly growing RTR 1/8-scale buggy category to break through the .21-size engine barrier.

KIT FEATURES

CHASSIS. Eighth-scale racing buggies require strong chassis to ensure proper suspension action and to withstand the often severe pounding that inevitably occurs when traversing uneven terrain at Oomph. With this in mind, the X-Terminator's 3mm-thick countersunk chassis has channeled sides to increase rigidity and molded mudguards to prevent the drive-train components from getting too dirty. This is standard buggy tech, of course, but the finish on the X-Terminator's aluminum chassis is unique. It's a hard coating of sorts, but it looks almost galvanized. Equally unique is the aluminum upper deck that places the steering and throttle/brake servos as close as possible to the chassis centerline and houses the receiver and onboard battery pack in separate molded boxes. The battery and receiver boxes are extra roomy and feature really handy snap-shut lids for easy access-no screws or body clips to mess with. The unconventional servo placement also seems to considerably simplify the steering- and throttle-- and brake-linkage routing. Front and rear torque rods provide additional rigidity for the chassis.

DRIVE TRAIN. Like most racing buggies, the X-Terminator features a shaft-- drive 4WD system with front, center and rear gear differentials and front and rear disc brakes that allow individual brake-bias adjustment. The diffs are O-ring-sealed, which means that they can be filled with thick silicone oil to aid tuning. The disc brakes feature highly polished steel rotors and steel calipers with fiber pads. Molded brake guides prevent the rotors from wobbling too much on the hex-shaped center outdrives. There are two brake discs-one for the front and one for the rear-and the molded rotor guides are able to accommodate extra discs, just in case you get the itch to run quad discs for extra stopping power.

Thick, steel dogbones extend from the center diff and are connected to the front and rear diffs via outdrive cups that mate with the internal, hard-- steel ring and pinion gears. The center diff is equipped with a steel, 43-- tooth spur gear. CV-style axles drive the front wheels and feature silicone boots to keep the axles free of dirt and debris. Steel dogbones are used in the rear. The entire drive train and front and rear wheels spin on shielded ball bearings.

SUSPENSION AND STEERING. The front and rear lower H-arms pivot on 3mm-thick hinge pins. Setscrews threaded into the front and rear suspension arms allow droop adjustment. Two lower shock-mounting positions are available on the front suspension arms, while the rear suspension arms have four positions. Unique reverse-mounted upper front wishbones capture the C-carriers for extra durability, and steel turnbuckles allow camber adjustment.

The rear suspension uses a conventional lower arm/upper camber-link setup with large molded rod ends and adjustable tie rods. Several rear upper camber-link mounting positions are available on the rear shock tower and hub carriers, and three upper arm-mounting positions are possible on the front shock tower to adjust the buggy's roll characteristics. Adjustable steering links allow toe-angle adjustment, and cast-aluminum knuckle arms keep the tires pointed in the proper direction. An adjustable rear swaybar is also included to limit chassis roll.

Aluminum shocks are found at all corners. The shocks feature O-ring seals, silicone bladders and stainless-steel shock shafts with silicone dust boots. Snap-on preload spacers are included to adjust ride height. I particularly like that the internal shock pistons are retained with locknuts instead of E-clips. A conventional bellcrank/drag-link steering system with a built-in servo-saver pivots smoothly, thanks to the ball-bearing-supported aluminum drag link. The drag link also has several steering-rod mounting options to alter the buggy's Ackerman setting.

ENGINE AND ACCESSORIES. XTM's .247 engine provides the go power. This is one of the largest engines installed in any RTR 1/8-scale buggy, and the extra cubic inches are definitely noticeable when you goose the throttle trigger. The engine is equipped with a 9-fin heat-sink head; aluminum, brass and chrome (ABC) piston and sleeve construction; a 2-needle slide carb; and a pull-start mechanism. A 3-shoe clutch, aluminum flywheel and a bearing-supported, 13-tooth clutch bell are installed on the engine. An aluminum manifold, powder-coated, metallic-blue tuned pipe and large-element air filter are also included and installed for you. The engine's displacement is larger than is allowed by race-sanctioning organizations, so be sure to check with your local racetrack to make sure that it's OK to run with this larger engine before you fork over your entry fee.