drewblueeye

OK DAN628 i am going to take your picture you posted and fill you in with what everyone is talking about when they say there is no nipple on the turbo.

Mike@Forge

iTrader: (23)

Here's a little tidbit for you guys to chew on:

If the boost controller and bypass valve share the same reference from the intake manifold, you can figure that they are essentially sharing the same volume of air (pressure/vacuum).

When the boost controller (lock-ball-and-spring type) actuates, meaning when the spring allows the ball to come off of it's seat and send the pressure signal to the actuator or external wastegate, some of the "shared" pressure helping to hold the bypass/blow-off valve closed under boost is now momentarily diverted to the actuator or wastegate potentially causing a "flutter" in the seal surface of the bypass valve and a slight loss of boost pressure altogether within the system.

When the boost controller and bypass valve each have their own individual reference from the intake manifold, the possibility for this flutter is greatly decreased, however, it may still exist to some extent because both references are still sharing a given volume of intake manifold pressure.

It is always highly recommend to ensure that any boost controller is referenced from the turbo outlet nipple where available, or from the intercooler piping before the throttle body if no turbo outlet nipple exists.

This is also important in that the boost controller only ever needs to see a positive pressure reference, and never vacuum.

Boost Controller
Positive Pressure Only
(Turbo Outlet)

Bypass/Blow-Off Valve
Positive Pressure AND Vacuum
(Intake Manifold)

drewblueeye

mike,
to funny i read that same thing last night and when i did it clicked!!!! but thanks for looking out for us that have problems with our cars and not being one of those guys that thinks they are superior and try to cut us down. your a true friend

SLVRNBLK

iTrader: (169)

Mike Forge, you can chime in of course. Shouldn't you be running the blue spring instead of the yellow? I run the blue spring with one shim. No fluttering.

Mike@Forge

iTrader: (23)

That depends entirely on how much boost the car is making. Most Evo's are fine with the Blue spring up to about 24 PSI or so.

drewblueeye

mike,
i have the yellow spring in and i still get a flutter. i have tried every spring with every combination of spacer.... yeah i had a few hours to waste. still flutters though. But if i but that Forge RS BOV will that fix my flutter?

dan628

iTrader: (5)

dude, are you still having problems??? what ever happened to your other post where you were making hardly any power and you though it was your tune. If you are going to buy another BOV I highly recommend the APS BOV, its been proven to work over and over again, maybe thats been your problem all along???

bigric09

iTrader: (37)

use a larger T much larger than the hose, that should help

KazzEvo8

iTrader: (2)

From all I'm reading here he DID NOT LEAK. Boost leak testing was good to 24 psi. He's describing a flutter or bouncing of the spring in the BOV at part-throttle acceleration - part-throttle acceleration that's hard enough to incur boost.

I have the same damned issue and I hate it. When I moved to the BR turbo outlet pipe (Lower IC Pipe WITHOUT THE NIPPLE which stock has) and from the stock boost solenoid to an aftermarket BOV it started. I've tried Forge and APS and it's not as bad with the APS, oddly enough.

I've seen threads here that recommend tapping the BR LICP and installing a proper nipple to resolve the problem and some have had success with it.

Mike's post, I believe, is DEAD ON. Thanks for the clear explanation, MIKE!

I'll be doing this as soon as I get my daily driver back on the road.

Peace!

drewblueeye

hey kazzevo,
i know this isnt a complete solution but i put the factory BOV on and there is no flutter, BUT i completely belive that the solution is to put a nipple on the BR LICP, just have the factory nipple cut off the factory pipe and have it welded on the BR LICP. That is the best thing to do

KazzEvo8

iTrader: (2)

My factory BOV leaked at <10psi - it's gone bye-bye a LONG time ago ... but thanks.

justchil

iTrader: (44)

Old thread but where in the heck can I get a "nipple" or "barb" to screw/weld in to the lower pipe. I've been looking around and this is all I've found:

http://boostcontroller.com/index.php...category%3D104
which is too large...

http://www.atpturbo.com/Merchant2/me...egory_Code=FTG
this may work.. not sure yet

I'm using 4mm vac lines and would prefer not having to have it welded...