When I first put the T-trim blower on . I had a little flutter from 3000 to 3500rpm's under light throttle . I adjusted the BOV [ out ] and it took care of it . But since I went to a bigger IC , the flutter returned and I just cant seem to get it adjusted right . Adjusting in or out only moves the flutter up or down in the rpm range . I've tried different vacuum ports to see if one provided more vacuum than the other with no improvement . I might try a bigger vacuum line to see if that may help . Oh...I do have after market cams so vacuum is at...12 to 13 in. at idle

ANY IDEAS ?????

 

Hey boog, ive had the same issue with the flutter/whistle since the get go. Ive had the type s bov on which still flutters/whistles, but not as bad, and recently vortech sent me a new spring for the maxflow bypass valve. I installed the spring and now there is no flutter or whistle. I believe the spring was rated at 4 inches h/g or something like that, its definitly softer. You might wanna try this as its only 15 bucks.

 

How did you get the S type to stay open under vacuum ? [ to vent ] I tried it and could never get it to work . Even took out one of the springs ........................................................... I moved the vacuum line to a bigger port and will try to adjust it some more to get it to stop the flutter .

Freez...The flutter comes from the bypass being on the edge of opening or closing...the flutter is compressor surge . If you have the adjustment to tight you will get the surge [ flutter ] when boosting and letting off the gas . I get it when not in boost at light throttle

 

Have you tried a larger valve. If you are surging no matter how you adjust the valve its likely not big enough for the blower you are now running. I could probably get you set up with a Godzilla valve from Turbonetics for testing. Its a full 2" (45mm) valve. If you still surge with that nothing will fix it
http://www.turboneticsinc.com/valves_godzilla.htm

 

Thanks Mia
I dont know if Im looking at it right . But my flutter problem is at light throttle and under Vacuum . Not after letting off the gas when in boost . It seems that after I put in the bigger IC that allows for more air flow....the preasure on the bypass valve is less . You need enough air preasure on the pipe side of the valve and enough vacuum on the other side to keep it open

 

Gotcha..I misread your original post..please disregard then..

 

I didnt have any prob with the greddy type s. I too took out the inner spring to see how it would perform. Ive never had flutter under boost, just when feathering the throttle lightly like you.

 

I may take it apart and clean it real good . And see what happens

 

Mine does the same thing, at light throttle in will pulse open and close. At mod to high boost it will open, bled off then when pressure and rpm drops it will start to pulse open and close again! I can't adjust it in any way to get it to stop this.
I tryed a Greddy type -S, it had a different sound but acted about the same. Hope it's not hurting our compressers!

 

I only had the new spring in one day on a permit last week, so it was hard for me to fully evaluate it, but i dont recall any flutter at all anymore. I also have only about 5 threads showing on the adjustment because of the weaker spring.

 

Thinking about your greddy bov tonight and wondering if you had the rs not the type s bov. I dont recall anyone else having trouble with the type s

 

I still have Greddy, I'll try the spring removal and see how it works, seams like it has gotten worse with the 2.87" pulley.

 

It kinda sounds like an exhaust leak and I hate it

I keep backing out the adjustment [ out to 9 threads now ] and still doing it . Im going to call Vortech this afternoon and talk to Steve and see what he thinks .
Are you guys running cams also ? Was thinking it might be the low vacuum from them thats not keeping it open

 

Just sent you an email...

Steve @ Vortech

 

on the phone calling you .....waiting for some one to answer....on hold

 

 

Taken care of...new spring on the way . Great service

THANKS STEVE !!!!!!

I will let you know how it turns out

 

Bill, wtf was the fix? Am I going to hurt my charger from the surging? @ low rpm?

 

Steve is sending me a lighter spring for the bypass so it will take less vacuum to open up

 

I got the new spring in the Bypass valve today . I havent tested in yet , but I can tell its going to take alot less vacuum to keep open . ANy one with cams should think about the lighter spring