The Myna pump can supply far more fuel than a non-turbo engine can use. You'd need more airflow. It probably would provide a power gain, but not much, even in the baseline setting it would probably smoke. The turbo engines normally have an excess air supply, and they can easily get more airflow by increasing boost pressure. You don't have that option on a normally aspirated motor.

617 engines are cheap these days, just buy a 617 turbo, plus this Myna pump, and swap it into your W115. Then it will be a rocketship!