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| issue 96, november 2003 |
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Features Suspension • No new trails were blazed by the X-Cellerator in terms of suspension design, but that’s not to say that the truck’s suspension isn’t among the nicest in its class. At first glance and even after a good amount of inspection, I noticed that the suspension looked very nicely refined. Adjustments are all over the place. Rear toe, anti-squat, roll-center, camber, and shock angles are all adjustable. In the front kingpin, ball studs are used along with variable camber mounting locations on the shock tower to allow for roll-center adjustment. To adjust the truck’s steering, shock angles are also adjustable. Speaking of shocks, XTM provides a full set of threaded body, aluminum, and bottom-loaded shocks. All four shocks have silicone boots to help keep the oil clean and the shocks moving freely. The shocks use springs available for Associated shocks. That means that there’s already a ton of shock tuning options available. Some of the nice touches that I noticed on the suspension that would fit in the “refined” category include the front suspension pin brace that’s screwed to the bulkhead. This helps to spread the load when called upon. I also noticed that the ball cups have a slight taper on them. This helps to beef up the area where the turnbuckle is being threaded to help prevent a stripped out ball cup. Also, the material used on much of the suspension is a very firm, inflexible material that, I found out in testing, is also very durable. Drive Train • The X-Cellerator’s drive train starts out from the engine and a two-shoe, sprung clutch. From there, the 16-tooth clutch bell rotates the 46-tooth spur gear. Both gears are 32-pitch, so you can use other clutch bells in 32-pitch. The spur is sandwiched by an adjustable dual-pad slipper clutch. The spur’s top shaft routes into the transmission. The internal ratio of the transmission is 3.31:1. It’s your standard three-gear configuration and sits nearly flat to help keep the CG relatively low. All three gears inside the transmission, like the rest of the truck, are ball-bearing supported. Power is finally transferred out of the tranny via an adjustable ball differential. To route power from the transmission to the wheels are steel CV-style axles. The axles accept all the wheels available for the Losi XXX-NT. To bring the truck to a halt, a fiberglass brake disk is located just behind the spur gear and surrounded by a pair of brake calipers. A large metal brace connects the transmission to a molded brace coming off the chassis to minimize any chassis flex between the engine and the spur. Flex between the two can mean no teeth and a trip to the dentist. Steering • The steering system on the X-Cellerator is fairly simple and straightforward. Two bell cranks, one of which is sprung, rotate on a pair of axles and connect to the steering spindles. Ackermann is adjustable as is the tension on that servo saver setup. Electronics • The X-Cellerator comes with a Hitec Lynx two-channel AM radio. The radio has the basic adjustments you might need. For steering and throttle, a pair of Hitec HS-311 are used. The servos are standard in the speed and torque departments. Power • Powering the X-Cellerator is an XTM .18 racing engine. It’s a standard, small block but bored and stroked to .18 displacement. The fact that it’s a small block is nice since you could easily swap it out for a .12-size racing-legal engine and probably not have to do much in terms of mounting and flywheel. In fact, XTM designers had that option in mind when they placed the engine where it is. The stock engine’s pull-start hangs off the side of the chassis thanks to a cutout. This means you don’t have to buy a smaller flywheel or engine mounts if you decide to go the legal route. As for the stock XTM .18, it’s made of ABC construction and comes with a large heat-sink head and a rotary-style carburetor. Body, Tires, and Wheels • The body on the truck is a generic-looking stadium truck body. It comes preprinted with a rainbow-themed paint job. It’s a colorful body—not the sharpest we’ve seen, but nowhere near the least attractive we’ve seen. Looking at the body, you’ll notice that the part number is molded into the windshield. This is to comply with new ROAR rules on bodies. Aside from the engine, the truck fits within all the ROAR rules for this class of racing. The tires on the truck are what you would expect from an RTR kit: firm enough not to wear out the first time you run the truck on the street, but soft enough that you’re not spinning in circles when you hit the dirt. In the rear is a spike/bar tread pattern that should work well on a variety of surfaces, and in the front are shallow nine-row ribbed tires that look as if they’re best suited for a dry, dusty surface. All four tires are mounted to white dished wheels. Instructions and Completeness • The instructions
that come with the Other Features • All of the hardware on the truck is American Standard. This is in keeping with the trucks that invented this class of vehicle. The fuel tank has no screws coming in from underneath the chassis; instead, two standers secure to the chassis and then screw to the top of the fuel tank. Fuel tubing routers are also used to keep the fuel tubing out of the way. As mentioned earlier, the entire truck is ball-bearing supported by shielded ball bearings, and all four wheels include bearing spacers so just in case you crank down a bit too far, you’ll do no major damage to the bearings. Testing Acceleration • Out of the hole, the X-Cellerator
was admirably quick—not ballistic, but by no means a slug. I think
this lack of real grunt is the transmission ratio. It’s a bit lower
than some of the more aggressive truck transmissions on the market. Once
the truck was rolling, the acceleration out of the corners was very
good. The .18 engine’s sweet spot appeared to be near the middle of
the engine’s power band, which is a good thing for a nitro stadium
truck. Top Speed • On the straightaway, I was able to
stretch the truck’s legs. The engine winded out nicely and topped out
just before the midpoint in the straightaway. The radar gun confirmed
that the Braking • On some of the large jumps, I used the
brakes to dip the front end of the truck. For that purpose, the brakes
worked flawlessly. Around the track, only one section called for
braking, and that was coming off the straightaway. Through my hour-long
run, there was nearly zero brake fade. The truck kept getting on the
binders with a very consistent tone. Low-Speed Handling • At low speeds, the X-Cellerator
was extremely sure-footed. On power, the truck dug in and went where I
wanted it to. Off power, it remained controllable with a neutral feel.
Turn-in was excellent, while turn-out had a slight push on-power. High-Speed Handling • At high speeds, the truck
was very sure-footed. Coming off the straightaway, I was able to pitch
the wheels and hit my mark lap after lap. The track was set up so that,
on more than a few jumps, as soon as you landed, you had to set up for a
turn. That meant that there were quite a few turns that most would
consider “high speed.” There was a slight push coming out of some
turns. I raised the rear ride height a bit, and this seemed to help the
turn-out steering a bit. Rough-Track Handling • The track was pretty well
groomed and didn’t have any “very” rough sections. There were some
ruts on the straightaway, and when I hit those at high speed, the rear
end seemed to bounce a little too much. I think going up 10 wt. on the
oil in the rear shocks would help to slow that down a bit. Other than
that, the truck remained very stable and handled the surface of the
track. Jumping • When hitting each jump, I let off the
throttle slightly with a minimal amount of drag brake in the setup. The
truck’s attitude remained nose up and very level from side to side.
There was one jump leading onto the straightaway that gave me some
difficulties. If my approach wasn’t straight, the truck wanted to push
out and tumble. Aside from that one jump, I would give the X-Cellerator
an “A” everywhere else on the track. Tuning • The X-Cellerator borrows a number of
design cues found on trucks originally intended strictly for racing. As
you can imagine, there are a number of options to tune on the truck
without spending a penny. The only tuning adjustment I needed to make
during testing was to the rear ride height. When I did, the truck
responded in a noticeably different manner. Thanks to all of the
possible adjustment points on the truck, tuning it to any track
condition should be possible. Damage • After running nearly two quarts of
Sidewinder through the truck, I’m extremely pleased to note that the
truck is still in one piece. The only casualty to report is that one of
the screws that holds the rear wing in place ripped out of the hole.
During our photo sessions, a driver needs to hit the same mark time
after time. Believe it or not, this puts a big strain on a vehicle.
Hitting a jump at a decent speed 15 times a minute for 10 minutes can
really tax a vehicle—especially since the idea is to get a cool photo,
regardless of whether the truck lands on all fours. Well, after a
half-hour-long photo session and lots of behind-the-scenes tumbles,
there were no broken pieces to report. Conclusion |
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alking
down the cereal aisle, you might find yourself looking at the
bagged cereal and wondering if that stuff is any good. The price
is right, but how does it taste? It looks like the more
expensive boxed stuff, so it should at least taste the same.
Then, you actually buy the bagged stuff, and you know what?
It’s actually pretty good. Sometimes, it’s better than the
boxed stuff. Well, the bagged cereal is kind of like the XTM X-Celleratror.
It looks like those more expensive trucks, and it’s definitely
priced right, but how does it taste? I’m here to tell you it
tastes very, very good. As you’ll read in my performance test
evaluation, the X-Cellerator is actually better than Fruity
Pebbles™ and at a Fruity Crisp Rice price.
