Vac on wastegate?
 

Ok, on a friends S4 TII motor I helped him remove all the emissions, air pump, PS, rats nest, and metal vac lines. We ran all of the needed connections like the fuel lines, OMP and lines, etc, but there is a line coming off the wastegate up close to the tranny and then to the back passenger side of the motor. It sits below the manifolds and is almost hidden. So my question now is where should I plug this in at? Is it a vac or a pressure line?
Thanks

That's actually not coming off of the WG, it's coming off of the twin-scroll actuator--which is the larger and the lower of the two brass-colored actuators below the turbo. It needs to see vac.

I've teed into the nipple coming off of the pass. side of the UIM, that you'll also tee the pressure-sensor, BOV, FPR and boost gauge etc. into. Everything works and I've got no complaints.

Maybe I'll go take some pics... :)

Its really not needed. You can remove it, or just wire it open. It is supposed to help direct air to the outside of the turbine, it never really worked well. They ditched it on the s5 turbo's.

Well, if you don't use it--it'll just be a restriction without any benefits. Plus, it's 'runner' is smaller, so to make it similar to the s5 turbo you'd have to port it out to match.

Believe me, if your T/S works there is a difference in spool-time from when it's connected as opposed to disconnected. Either way, it's as simple as connecting a vac. line. :dunno:

Erik just helped me do all the emissions removal on my car Hours ago, He is on it and knows whats up :icon_tup:

No batteries for camera. Heh, thanks B. I'm about to go get those O-rings for you... You n00b.

It is down charging @ the parents house I need to stop by and get it....and yes I must admit, I am a N00b :molepoke:

You shouldn't be criticising a system you don't understand. It doesn't "direct air to the outside of the turbine" (WTF?), it increases the exhaust gas velocity at low revs to spool the turbo faster, resulting in less lag. It worked fine, and was only deleted from the S5 because of the addition of a fully divided exhasut manifold and electronic boost control, both of which reduce turbo lag.

You can't port the smaller runner to match the larger one, there's nowhere near enough metal in the casting. All you can do is shape the runner's inlet for better flow.

It's definitely not as simple as connecting a vac line. Without the solenoid valve and check valve plumbed in correctly the flap will simply open as soon as you put your foot down no matter what the revs, which competely defeats the purpose of the system. The solenoid valve and check valve are what keep the flap closed below 2700rpm and open above that. The way you have yours hooked up means it'll be having little if any positive effect.

Thanks for the help

That sucks. Do you have any pics of the solenoid and/or check valve?

It's very easy to set up. Look at the schematic on page 4B-53 of the FSM and plumb it up exactly like that. Note the orientation of the solenoid valve and make sure the arrow on the check valve points towards the manifold. I zip-tied the solenoid valve to a brake line on the firewall.