Fluttering sound on shift
#33
Burning Brakes
Join Date: Apr 2004
Location: Orangevale, CA. USA
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so the fluttering is louder as boost increases...now does it flutter pause then whusshh as boost gets higher or does the flutter last longer and then the whussshhh?
#35
Burning Brakes
Join Date: Apr 2004
Location: Orangevale, CA. USA
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I think your BOV is not actuated fast enough somehow..what spring do you have in there...did it get better when you swithched to Tial from the Lindsey unit?...
#36
Race Director
Thread Starter
With the Lindsey, I never got any whoosh, and I didnt get a whoosh with the Tial till I took out the Lindsey vac hose and put in some thicker walled and bigger ID stuff on. As I said the line now is 5mm in ID and only 35cm from the manifold and is a dedicated line! Maybe the banjo bolt fitting is restricting or faulty?
I have the stock Tial spring 13lbs I think... refer previous post.
I have the stock Tial spring 13lbs I think... refer previous post.
#37
Burning Brakes
Join Date: Apr 2004
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your BOV is not being actuated enough...1)you will have ot check your fittings and lines and make sure the vaccum is getting to the BOV to actuate it
2) make sure the spring rates are compatible with the pressure....too much spring would cause a delay in opening wich cause the flutter/surge and finnally when oppened the whussshhh...make sure the spring is ston enough to keep the BOV closed in boose but also light enough to open as easy as practicable when you let off the gas and vacuum is created...
somewhere in that system is your problem...gotta be.
check fittings and hoses..any restrictions..dirt...not allowing propper vaccuum
2) make sure the spring rates are compatible with the pressure....too much spring would cause a delay in opening wich cause the flutter/surge and finnally when oppened the whussshhh...make sure the spring is ston enough to keep the BOV closed in boose but also light enough to open as easy as practicable when you let off the gas and vacuum is created...
somewhere in that system is your problem...gotta be.
check fittings and hoses..any restrictions..dirt...not allowing propper vaccuum
#38
Burning Brakes
A weaker spring helped a little when I ran a big turbonetics BOV. Could never get a nice wooshing noise though. Someone told me that the flutter (turkey gobble) noise is actually from the compressor wheel (surge). I could never get rid of it with the BOV's I tried no matter how fast I tried to get them to open with week springs and bog bore piping to the inlet manifold.
#39
Race Director
Thread Starter
Hmmmm at 25 a pop I dont want to try the gammet of Tial spring rates! Anyone know how to determine scientifically what spring rate is required to hold 20psi shut and actaute in time?