Modify the Behavior of a UT2004 Model

Not satisfied with new art? Add new behavior!

Other hacks demonstrate how to model a 1969 Plymouth Barracuda ( [Hack #82] ) and how to turn it into a playable Actor in Unreal Tournament 2004 ( [Hack #83] ). This hack builds on that to add nitrous-style speed boosts to the ‘Cuda using UnrealScript.

While it isn’t required, you’ll have better luck understanding this hack if you understand high-level object-oriented languages such as Java or C++. Being familiar with vector math and basic physics will help, and a working knowledge of UnrealScript and how “replication” (the Unreal networking idiom) works is also beneficial.


Download the source code mentioned in this hack as well as the art packages necessary to use this example from

What Is Nitrous?

Nitrous is short for nitrous oxide, a gas that produces a significant horsepower boost when injected into a gasoline engine. Street and drag racers often use nitrous to add speed boosts at key moments. In general, you cannot carry enough nitrous oxide to use it at all times. For more information on how nitrous oxide works, see its How Stuff Works page at

In this example, you’ll simulate the use of nitrous for the ‘Cuda. You’ll add a short speed boost when you click the left mouse button (by default, the AltFire key). During the boost, the ‘Cuda will accelerate rapidly, and flames will shoot out of the tailpipes. ...

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