Changed BOV and boost went down?

[JMiller]

Ok i had the type-S BOV on my car and my boost was set at 15psi with a mbc for the past 2 weeks it didn't seem to be opening like it should so i put my SSQV bov on and did a BLT everything was good so i went to test drive it and it was only boosting to 10psi. What could have caused this.(the ssqv bov is vented, the type-s was recirculated) Any help would be great, Thanks.

 

[bling5tatus]

spring pressure too weak inside one of the bovs?... sounds like one of them is being blown open or the diaphragm is torn or something.

 

[DSM4me44]

...it didn't seem to be opening like it should...

What do you mean by this? I am wondering because I have a Greddy Type S as well and haven't had an issue.

 

[JMiller]

Yeah my "eBay" type-S wouldn't open right at 12-15psi, how would that cause it to boost higher than the HKS bov.

 

[JMiller]

at higher boost the extra air thats supposed to come out of the bov was coming out of the turbo.

 

[Dsmj89]

at higher boost the extra air thats supposed to come out of the bov was coming out of the turbo.

That's compressor surge. Sounds like your bov was set too tight, pressure inside wasn't strong enough to blow open through the bov and made it's way out through the next available exit, the turbo.
If you loosened it up a bit it might have helped. Worst case scenario the spring was probably done for.

 

[JMiller]

I did loosen the spring but that caused it to open to soon, i spent days trying to get that spring at the perfect spot but couldn't.

 

[Dsmj89]

That's ebay quality at it's best, you get what you pay for sometimes.
As for the hks, is it the adjustable one ?

 

[JMiller]

The type-s actually has been on there for the past year and a half with no problems, and the hks is the new type(non-adjustable)

 

[Dsmj89]

There shouldn't be a problem with the hks then, that's my favorite bov.
Guess the spring on the bov just went out after all it's use. HKS ftw.

 

[JMiller]

So how would the bad bov cause the boost to be higher than with a good bov?

 

[Dsmj89]

That's odd. Have you checked for boost leaks ?

 

[JusMX141]

By chance, are you teeing your boost controller into the blow off valve line?

 

[JMiller]

No my mbc is connected to the compressor housing and i boost leak test up to 25psi with no leaks.