Thread: GTIR Intake Manifold BOV/Vacuum Routing Question

Hey guys, I was looking over how to eliminate some of the factory vacuum hose/hard pipes in front of the injectors for each throttle body on the manifold, and wanted to make sure I have this correct before I drop the motor in the car in the next few days.

In this thread:

Blow off valve vacuum hose setup | Canada GTiR

the guy makes his own vacuum line/t fittings and connects the vacuum lines from all 4 throttle bodies to the BOV instead of using a line off the factory vacuum block behind the manifold. It looks like this is the proper way to get the vacuum to the bov from all 4 instead of just 1.

Here is what I am dealing with now:



My question is, does that t fitting/vacuum hose setup shown above really make a difference in the bov/response? Is just capping off the line that comes from the pcv of the valve cover the right way to do this? I went through the trouble of tucking the injector harness, so I want to make the vacuum lines as clean as possible without sacrificing any performance. In actuality I would rather improve it if that's what this really does. Can all of those red autobahn hoses I have be eliminated?

For reference, my bov is currently venting to atmosphere in the factory recirc location on the intake mani. I plan on having the maf in blow thru configuration in the piping leading up to the intake manifold.

Thoughts/opinions/suggestions on the best way to do this? Thanks in advance!

After a bit more reading it looks like just capping the pcv off is a bad idea since obviously the crankcase has to vent. Not sure why the guy did that on the other gtir forum.

I guess my question is where to vent the pcv valve to if I eliminate all the hard lines and factory hoses with my own t fitting/hose setup to the bov like in the write up?

catch can possibly

Is routing all 8 of the quad tb vacuum nipples to the bov ideal? I've read a few places that those 4 are SUPPOSED to be capped off.

Just want to do this right.

i have no idea i stay away from the gtir for this exact reason.

Lol I do agree that all the vacuum crap on this engine is a pain. That's why I am trying to eliminate what I can.

I understand everything else in terms of the motor except for the damn vacuum.

That intake manifold makes my brain explode. Good for turbo, though.

You could always ask on the GTi-R Canada forum. Lots of input there.
There's been a lot of discussion about the PVC valve and how different folks plumbed it. Since then I've plumbed the PCV valve back into my vacuum header.

i just slapped on a set of trumpets on the gtir intake manifold and converted it to n/a with a map sensor and high comp. i wish i could help about vacuum but that manifold is crazy. there are like 12 vacuum ports lol

Can't wait to see how this ends up, i've been dying ti find out a neater way to route the hoses on mine