Fiat (and other's I'm sure) have the [MultiAir system](https://www.caranddriver.com/features/a16580674/fiats-multia...) which doesn't use cams to actuate valves

And here's an example of someone that retrofitted a Miata to use a similar [air-actuated valve system](https://youtu.be/E9KJ_f7REGw)