vacuum lines

bluesubaru · Post by **bluesubaru** » Thu Feb 03, 2005 6:09 am

What/Where did you all tap your vacuum lines for your boost guage and bov? I tapped mine from all the way on the other side of the engine bay.

It reads 20mg of vacuum and +boost just fine. But I want something closer and cleaner, I know the intake manifold has a few of them. I can supply pics if needed.

boostjunkie · Post by **boostjunkie** » Thu Feb 03, 2005 6:21 am

I tapped mine into the vaccum line from the resonator box on the intake to the manifold. Just t into that line.

BAC5.2 · Post by **BAC5.2** » Thu Feb 03, 2005 6:37 am

There is a line coming off of the #1 intake runner. Tap into that one, and your set. I might have a picture somewhere...

J-MoNeY · Post by **J-MoNeY** » Thu Feb 03, 2005 6:37 am

I did a search and found this illustration by vrg3. Hope de doesn't mind me linking this guy to it.

He has it circled. Go and get some side cutters and snip the line in half. Get a "t" vaccuum junction at your local Checkers or whatever, then run that line to your guage.

vrg3 · Post by **vrg3** » Thu Feb 03, 2005 11:14 am

Yeah, all three of these guys are both suggesting a common place to hook the boost gauge up. It sounds like that's what you're using already.

If you have the EJ22T intake manifold, there should be a nice 5.5mm nipple right below the brake booster nipple. This is meant for the blowoff valve. It's a better choice than the other one because it's near the throttle body and is larger.

bluesubaru · Post by **bluesubaru** » Thu Feb 03, 2005 4:17 pm

the pictures in this thread is exactly where I have mine tapped, I was looking for a spot closer to the brake booster or on the driver side of the car. Thanks for your help!

azn2nr · Post by **azn2nr** » Fri Feb 04, 2005 12:56 am

i have mine taped there but im gonna swich it to the bov spot soon.

BAC5.2 · Post by **BAC5.2** » Fri Feb 04, 2005 7:31 am

bluesubaru · Post by **bluesubaru** » Sat Feb 05, 2005 4:48 am

why, is in reply to what post?

BAC5.2 · Post by **BAC5.2** » Sat Feb 05, 2005 5:59 am

No, why would you move from the runner, to the BOV feed line?

What is the point?

bluesubaru · Post by **bluesubaru** » Fri Feb 11, 2005 3:39 am

I am having bov surging problems, and I have adjusted the bov so many times, and still cannot get it right.

I ordered a ej22t intake so I am going to run the greddy type s bov recirc. soon.
But I cant seem to get it right. Is it becuase its made for a WRX (14psi) and I am only pushing 5psi?

vrg3 · Post by **vrg3** » Fri Feb 11, 2005 3:52 am

It's not clear to me that it's even possible to set up a BOV to stay shut at idle but also open under all conditions that could cause compressor surge.

bluesubaru · Post by **bluesubaru** » Fri Feb 11, 2005 4:01 am

right, but it seems when i adjust it it either idles fine, but when i hit any boost it surges.
or when I adjust it again it idles like crap, but blows off fine.
I am hoping the recirc will help.
I heard I can tap a vacuum source for the bottom small nipple on the greddy type s (which is usally left open to suck in air) so to help it get more air faster.

vrg3 · Post by **vrg3** » Fri Feb 11, 2005 4:24 am

Right, that's what I'm saying -- it simply may not be possible to set your valve to both not leak at idle and fully prevent surge.

I'm sure a recirculating valve will help. You can set it to open at a small enough pressure differential that surge won't happen. It'll open at low loads (like at idle), but that'll be just fine. In fact, it will in theory allow the turbo to spool up slightly faster by equalizing the pressure on both sides of the compressor.

azn2nr · Post by **azn2nr** » Fri Feb 11, 2005 4:58 am

i readjusted my rfl and it works fine now. closed at idle and open under all stiuations that it needs to be.

to answer phil. my engine bay is soo cluttered and moving it is just an attempt to clean things up a little

bluesubaru · Post by **bluesubaru** » Fri Feb 11, 2005 5:26 am

okay, thanks, i will see what happens.
But would the fact that its a WRX bov made for 14psi and the spring is set so stiff for that.
Would my 5psi setup make it harder to work right?
Would I need to trim the spring a little?

vrg3 · Post by **vrg3** » Fri Feb 11, 2005 5:51 am

WRX blowoff valves are meant to go on the intercooler's outlet end tank, aren't they? So they shouldn't need excessively stiff springs.

bluesubaru · Post by **bluesubaru** » Fri Feb 11, 2005 2:22 pm

it is on the IC, but if WRX have 14psi to push the spring open and I have only 5psi, it may not opne , hence causing surge.

vrg3 · Post by **vrg3** » Fri Feb 11, 2005 4:46 pm

The valve acts on differential pressure between the inlet and the manifold reference. The differential pressure between the intercooler's end tank and the manifold is very small, even at the flow rates achieved by the WRX's engine.

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vacuum lines

vacuum lines