QGMika

Anyone bypass the N249 so that the DV receives direct vacuum from manifold?

Afrosquad

Yes, works fine

QGMika

other's said that my mbc was turned too tight...which i can agree with, but i decided to try bypassing the N249. A full flutter or compressor stall rarely happens now, but is replaced by a split second flutter sound, and the normal rush of air...So i guess as long as i never hear a full flutter anymore, it should be better..

Lightweight-USPowah

Depending on the spring rate inside my FOrge DV, I get the flutter.. I am definitely hearing the dv or maybe something else open on partial throttle because I can hear the air rushing through.. It seems as though sometimes it stays open on WOT.. : / Interested to hear about the install...

Yippers®

idle and partial throttle unless you are at 0 inches or positive pressure.

xr4tic

N249? Whats that for?

Audi2ptzero

IIRC it is just a valve that connects the intake manifold to the bpv and then also controls the secondary air pump valve on the back of the head.

QGMika

#23 is the N249 valve and #16 is the N112 valve which controls the secondary air pump. Anyhow, there is a vacuum line that goes from #23 to a vacuum port at the edge of the manifold. And also a line from #23 to the DV. So remove and cap the line that goes to the manifold with a screw...also remove the DV line from #23 and attach it to the port at the edge of manifold. Finally, cap the output port of #23...

<img src="http://pictureposter.audiworld.com/AudiWorldPics/2000/Vaclayout.gif">

Afrosquad

Or you can loop the N249 input/output ports with a vac line

Lightweight-USPowah

I can hear the air being dumped into the intake track.. If Im in 4th at 4000rpms its quiet as a.. : / I dunno what to compare it with but its real quiet.. Its slow as hell when the air is being dumped back to the intake.. Any ideas as to why the car would do that?