What does the brass restrictor in the pipe to the actuator on the VF28 do?

Would a lack of this restrictor cause the turbo to produce less boost at high revs?

Damo

 

In layman's terms it limits the amount of air sent to the actuator to allow higher boost pressures to be run.

It is an essential part of the boost control mechanism, without it the boost control solenoid can't bleed off enough air to make the desired boost.

Andrew...

 

Does this mean it would loose boost at high revs without it?

Damo

 

It would mean it would be down on boost all the way through the rev range...

 

My car is mapped to run 1.4bar in the midrange but then it tails off to 0.8bar at teh red line, so the boost is leaking from somewhere.

Could this be the problem?

It has been on the rollers and it isn't the mapping, it just won't hold boost above 5000rpm

Damo