Tial BOV Issues w/ Automatic??

[TURFNNSURF]

Here's a question for Anyone.

I have a 1G auto and when letting off of the gas I have a slightly different BOV situation. Since the car is always in "gear" when the throttle plate closes I see as much as 25inHg under load, but at Idle with my FP2 cams I see 13-16 inHg. At full throttle both my 7 and 11 psi springs hold closed all the way to 7000rpm at 26+psi boost. However, I am having part throttle acceleration flutter with the 7psi spring(less than 20psi boost). The 11psi spring has VERY minimal accel flutter, but has MAJOR "BOV FLUTTER" when letting off the gas, at any boost under 20psi. When choosing a Tial spring, what vacuum should I choose for? Tomorrow I was going to pick up a 9psi spring and try it. Maybe that might be the answer for my situation, but any input would be helpful.

Thanks

 

[black91awdturbo]

Most people with Tial bov's don't usually have the correct spring in it. All Tial's come with the 11lb spring which will not begin to open till 21inhg vacuum, and fully open at 27inhg vacuum. I usually recommend the 7lb spring for 4cylinder cars which begins to open at 15inhg vacuum, and fully open at 21inhg vacuum. Any other spring will cause compressor surge. The 7lb spring can still hold 28psi before leaking by itself, and with pressure going to both the valve side and vacuum nipple the valve holds 38psi. Which is more than enough for any street driven car, if it is track dedicated I say the 9lb spring is the next step.