Forced induction Question

[Landshark1342]

Hi im new to the site and i have a forced induction question. How is servo assisted brakes which is assisted with inlet manifold vacuum affected with forced induction? The inlet manifold has positive pressure as opposed to vacuum. How is the brake servo assist maintained? Not including pump assist?
Cheers Jimmy

[Black Lotus]

Power brakes have a vacuum reservoir with a check valve. So in all non-boost driving, the reservoir builds vacuum, then as soon as boost builds in the intake, the check valve shuts preserving the vacuum in the reservoir.
You're probably in trouble going downhill with a tailwind if the throttle sticks wide open 'tho.
This check valve goodness can also work with the PCV system and the carbon cannister.

[Landshark1342]

Black Lotus,

Cheers for the quick reply! That makes sense, on off boost driving even overrun will be enough time to fill the reservoir.
Cheers