After a bit more research I've found our cars tend to idle around 20in/Hg (sea level?), so it looks like the pink should be what we want..

These are the three different springs offered by Turbosmart, with their respective vacuum pressures.

BOV Kompact Soft Spring-Blue
TS-0203-3001
Vacum High -13InHg, Vacum Low -3 In Hg


BOV Kompact DP Spring-Pink (included with valve)
TS-0203-3002
Vacum High -24InHg, Vacum Low -14In Hg


BOV Kompact PB Spring-Green
TS-0203-3003
Vacum High -19InHg, Vacum Low -9In Hg

So with this pink spring in, your not getting mad chatter/flutter? Mine was so bad I couldn't even drive the car out of embarrassment. I needed the blue spring, plus I had to trim it down even. Its holding all 10psi of boost also.

Success!!!

Finally got it running like the bosch valve. It did require me to use the pink spring, the blue spring was just way too soft and it wouldn't close when it needed to under light load. Bit weird that you're running more boost and had to use a softer spring than I did... Maybe it's cause you're on an upgraded block? Or due to where your BPV is located in the air to air setup? Not sure.

I popped in the pink spring, set it about 2 turns harder than the softest position. This was a little bit too tight, as the valve wasn't opening at idle. So I softened it a little more and eventually got it damn close to perfect. Took it out for a drive after cleaning exhaust tips / bumper, and no more nasty exhaust soot going everywhere. Will have to grab a datalog with cipher but seems like a/f is in check again!

My current set up is the pink spring with no spacers, about 1/2 turn harder than fully soft on the cap. Maybe the green spring would be our ideal choice to have a bit more room for adjustment.

BOLIO, what I would recommend if you want to try it is buying the valve and adjusting it with the pink spring first, if for some reason you need it to be softer like topgunz, you can either trim the pink a bit or buy the blue or green one, but honestly I didn't need the blue one at all. Green might have been nice. Would have resulted in much less of a headache if I started with pink instead of blue :roflpuke2:

So so sooo happy that it is running great again

As far as flutter with the pink spring, under normal driving i've been having clean vents free of flutter. There was one specific scenario where I vented it around 6500rpm testing it, and under that load I was getting some flutter which means I have to go just a bit softer. But from what I read on the Evo forums was these springs tend to 'break in' and soften up a little with regular use. So I'm going to wait at least a few days before I try to soften it any more to let the spring get settled in. Next few days will just be driving to the office so I won't be driving like a bat out of hell anyways :tup:

And damn does this thing sound good, can't imagine the sound with the vortech race valve that Top suggested.

Thanks again for all your help guys, without the support on the forum I probably would have just returned the valve and tossed the bosch one back in.