Most manual boost controls have a little bit of a problem. They’ll allow a little spike before they settle down to the set boost level. Not this one – in our testing, the boost rose directly to the target boost level and stayed there. When you’re setting the boost, there’s no guessing – the knob clicks into different settings and the controller is even well labeled so you know if you’re increasing or decreasing the boost. It’s very easy to use.
Because of how it works, the boost controller will improve boost response even if it’s at the same peak boost level as running just off the wastegate. It keeps the wastegate closed until the target boost is reached, normally the wastegate would start opening earlier and bleeding boost.
As with any boost controller, this can only raise the boost level from what’s allowed by the wastegate. It can’t lower it. Even when turned down all the way, it will increase the boost over your current wastegate level. They may require adjusting with large altitude changes of several thousand feet.