More importantly it needs to be properly adjusted so that it vents efficiently when required. Don't screw with the adjustment is the usual approach - unless the mfr/vendor/installer knows and says differently.

 

I was playing around with adjusting the spring last night. I think what it does is adjusts how much is VTA and how much goes back to the intake. I had tightened it up and I could only hear it at higher RPMS, now I loosened it back and it is a lot louder and you can hear it at lower RPM's. I am thinking with the tighter adjustment it gives more back to the intake, like it should. It seems with the looser adjustment when you shift sometimes it is jerky and there is this bang sound, but with the tighter adjustment it seems to shift smoother. Any thoughts on all of this?

 

This was my first mod on my evo. Stock it is very quiet. If your looking for "sound" then install a intake and you will get what your lookin for.

 

Yea, same thing with me. When the spring is loose, the car jerks but you get a louder sound at lower rpms but when the spring is tight, you get quieter sound and shifting is really smooth. I personally had first hand experience when the first time I installed this bov the wrong way. The car jerked like all hell and I got this flutter sound. BTW, when you loosen the nut, doesn't it fall off when you shift? I tested this in my garage when I loosened the nut, and reved the engine, the nut almost fell off.

 

You have to loosen the nut, then use an allen wrench to adjust the screw, then make sure to tighten the nut up before turning on the engine.

 

Driveability is all that suffers when you adjust it. My experience says the APS out of the box is perfect, no adverse driveability and IN MY CASE was a huge sound adjustment - although that's not what I was looking for, it makes my kids smile.

 

Why do you say suffers? I think it made it better when I adjusted it to be honest with you.

 

I wouldn't say it's pointless to change your stock bov. With all of the leaking problems they have, I'd change it. Hell I just bought a 1g DSM bov for mine. I got it for 15 bucks. All I have to do is buy the flange and I'll be good to go.

 

OK, driveability suffers when it's poorly adjusted, how's that? *Chuckle*

I know the change from the crappy stock to the APS made my driveability better and I didn't adjust mine! =)

 

OK, whats the problem in this case.

I put on the APS with having the stock airbox, everything worked flawlessly, could only hear it under load in the higher boost levels, held boost great, and such.

I put the buschur intake on and now the APS can be heard in most shift changes and throtttle releases even in the lower RPM's AND i am getting this fluttering sound when i am in mid-to-full boost. It definitely sounds like what people are describing as the infamous flutter sound.

Now, the question is, was it there before but couldnt hear it due to the stock airbox?
Is the any resolution to this? I havent had any experience with this before now

Yes, it is hooked up properly!

Any opinions or ideas would be appreciated.

Thanks!!!

 

yes it was probably there with the stock air box, untighten the screw a little bit to get ride of the flutter, surge is not a good thing!! its hell on your turbo!!

 

I thought some BOV's make that sound naturally. I know the Mopar BOV for SRT4's make that flutter during low-mid boost.

 

Could it be the way i have my MBC hooked up. I have the MBC tee'd into the BOV. Could this cause the flutter??

 

Good question, i was also wondering that as well, maybe there isnt a problem just the typical sound it makes.

 

Yes, i usually don't hook up any t's through the BOV vaccum line, it needs as much as it can to open the valve correctly. I did that about 2 years ago with my last car and got rid of the surge