well i have noticed the turbo back spinning lately and seen there is different spring rates for the tial 50mm bov is this back spinning going to hurt the turbo till i get a spring for 7 psi . im only running 10psi and it opens when im boostin 5 to 10 psi but anything under 5 it will back spin the turbo.. please if anyone has any info let me know

 

Are you referring to compressor surge?

Try a stronger vacuum source.

 

measure your engine vacuum at idle, then size it with this chart to find the correct spring you need
the PSI ratings have nothing, zip, nada to do with boost
http://www.tialsport.com/docum...p.pdf

 

i don't think it would be very good, i'd get it changed asap.

 

my idle vac is about 18 in. i have a 7 psi spring in my bov. but at low boost around 5 psi my bov flutters. whats going on? the bov has its own vac source also

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">my idle vac is about 18 in. i have a 7 psi spring in my bov. but at low boost around 5 psi my bov flutters. whats going on? the bov has its own vac source also</TD></TR></TABLE>

you need an 11psi spring at that vac level (9psi if it is 17...i don't know what 'about' actually is)

 

correct we saw a k series car with great vacuum keep the tial open @ idle w/ a 7 psi BOV spring....

tial products gets a from us!

 

I had a 11psi spring and it was fluttering worse. thats the weird thing. it took alot ot get that bov to open. with the 7psi spring it barely opens at idle which i thought was what I needed? help?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TiAL &raquo;</TD></TR><TR><TD CLASS="quote">

you need an 11psi spring at that vac level (9psi if it is 17...i don't know what 'about' actually is)</TD></TR></TABLE>

 

measure your EXACT engine idle vac at operating temp, then go by the spring chart...the valve should not be open at idle, it should be on the verge of opening.

going by what you said, it sounds like you have &lt;17 in/hg at idle and the 9psi spring is the one you need...but measure your vac, do not guess and do not use 'about' as a measurement.