Getting TiAL 50mm BOV ... what spring should I get?

[fastcougar]

According to their website, TiAL recommends the following spring rates for their BOV based on warm engine idle vacuum. So, anyone care to guess the vacuum reading on an 8.8:1 CR 3L engine?

Engine Vacuum Reading | Use Spring
-22 and -23 in/Hg | -12 Psi (-24 in/Hg )
-18 and -21 in/Hg | -11 Psi (-22 in/Hg )
-14 and -17 in/Hg | -9 Psi (-18 in/Hg )
-10 and -13 in/Hg | -7 Psi (-14 in/Hg )

 

[BurritaSVT]

I know the 7 psi is not enought since i have it I had to put a washer and it still not stiff enough to keep premature opening. I ordered the 9 psi spring and i am still waiting to install it but I would go with the 9 psi or 11 psi because on deaccelerating the car gets up to 20 vac and it will allow unmeasured air to screw up the a/f. Trust me with boost pressure on one side and vacuum on the other the valve will open with a stiff spring.

 

[fastcougar]

Thanks ... it comes with the 11 psi spring as is, so I will go ahead and order it.

 

[Keyser]

On my 2JZ 3.0 I have an 11psi. 8.5:1

 

[shavedsvt]

i was told to use the 11psi spring. mine came with it.