Lets say we have an object that we have defined as a pyro emitter.
However when we run the sim, the flames/smoke hit the top of the container, damaging the effect.
In the network, expand the pyro sim node (by double clicking):
![](https://i1.wp.com/www.john-player.com/wp-content/uploads/2019/07/houdini-resize-pyro-container-1.png?fit=1024%2C600)
Select the pyro node:
![](https://i0.wp.com/www.john-player.com/wp-content/uploads/2019/07/houdini-resize-pyro-container-2.png?fit=1024%2C570)
Activate the modifier handles using the option on the left of the viewport:
![](https://i2.wp.com/www.john-player.com/wp-content/uploads/2019/07/houdini-resize-pyro-container-3.png?fit=1024%2C600)
Then use the red arrows in the viewport to resize the container:
![](https://i2.wp.com/www.john-player.com/wp-content/uploads/2019/07/houdini-resize-pyro-container-4.png?fit=1024%2C674)