# Ballast

Some competition will require that you meet a minimum weight, such as the [Rush SR Spec Series](/at-the-track/competing-in-events.md).

In this case, you may need to add ballast to your car. Ballast plates are widely available, we recommend the stackable "brick" type, pre-drilled so you can bolt it into the car.

The best mounting point is behind the seat, in the seat rails. This avoids upsetting the car's weight distribution and can be solidly bolted to the frame using M10 bolts.

Thanks to owner Andor Tobelem for the below photos and video.

{% embed url="<https://youtube.com/shorts/a-0Mz2Db--E?feature=share>" %}
Video by Andor Tobelem
{% endembed %}

<div><figure><img src="/files/xL9vur6H2dcjXa8bFhJu" alt=""><figcaption><p>Small blocks from above</p></figcaption></figure> <figure><img src="/files/Rnh82e8c0yi8nsH7hnmn" alt=""><figcaption><p>Large block bolted tightly into one rail</p></figcaption></figure> <figure><img src="/files/wX1TchyEUBE1zT5gIBJC" alt=""><figcaption><p>5lb blocks on seat rails</p></figcaption></figure> <figure><img src="/files/AFfL0xJB2of9jsPKnOMj" alt=""><figcaption><p>Blocks outside of car</p></figcaption></figure></div>


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