A magneto ignition system:

A magneto ignition system produces a hotter spark at high speeds due to its ability to generate high voltage directly from the mechanical energy of an engine's rotation. As the engine speeds up, the magneto system generates more electricity, which contributes to a stronger spark. This is particularly advantageous in high-performance engines where a robust ignition is necessary to ensure proper combustion of the air-fuel mixture. The increased energy at higher speeds helps maintain efficient operation, enhances ignition reliability, and can lead to improved engine performance.

The other aspects of magneto ignition systems relate to their construction and operation, such as producing AC power and the general design without requiring a battery or points, but the defining feature here is the output of a hotter spark at increased speeds, which directly impacts engine efficiency and performance.