My vortech is kinda hard to build boost. So today i played with BPV. I tighted it down till, umm still feel about four line on adjuster...Now i can hear loud hissing sound comming from BPV..did i tight it down too much??
If anyone could post up their setup pictures, that be great. Thanks guys.

 

Not sure on your bypass valve, but since your belts are new they will stretch and that will cause you not to boost like normal. Boost will bled off or not even reach your normal boost level . I know you tightened them once but check again to be sure.

 

maybe your bpv is going bad.

I have a 100% working one that I have no need anymore

 

lol i don't think so.

Edit: Btw, got an answer why it makes whilstle noise. But still not sure, where should i set this at... I called vortech, they told me i have to tight it down more...

 

remember, tightening it makes it close later, ie take longer to build boost.

its hissing because it cannot overcome the spring pressure and never closes completely.

i never touched mine from the factory and its worked perfectly. 6-7 threads showing has been the generic answer though. I just think you need to stomp on the gas harder.

 

Well, i just left it about 5threads. Now hissing sounds little reduced.

Gas harder..i can not push all the way to floor to build boost...that's only reason i'm doing this.. i can not push all the way to floor everyday just try to feel boost.......

Edit: so you are saying...i have to lose it more?

 

Frankie,
It was nice to talking to you on the phone again. About the rough idle.. i went look over all the bolts and installed. Everything looks fine. I haven't pick up stuff for leaking test yet. I disconnect the battery now, just try to see if i can reset, and i'm going to try throttle reset. If that both not work, i will have to check the leak for sure.

It is really weird, A/F is stays around 14~15 now...but still rough idle.

Edit: Do have a question tho, is it possible if there is damage on intake hose it could makes a rough idle?

 

Tightening it makes it close sooner and open later.

It is hissing because of the fact it can't open completely and the same amount of air is exiting through a smaller hole and thus increasing the velocity. Very similar to a whistle.

 

You will never hit boost unless you get the manifold pressure to 0psi allowing for the bypass valve to close. The reason you can't build boost at partial throttle is simple because the manifold is still under vacuum and therefore the bypass valve is still open dumping all the air that would make boost. The only time I have seen a supercharger build boost at partial throttle was when they had a restrictive bypass valve that could not vent enough CFM to keep up with the blower. That is a bad instance because it means that you may get compressor surge where the path of least resistance is backwards out the inlet of the supercharger .

 

So how many threads should there be in the BPV? mine is alllll the way! Iam going to adjust it to show 6-7 threads? is that correct?

Also when you adjust the screw do you also adjust the other bolt? because it feels loose, or does it automatically go up?

 

It is determined by the amount of air flow being vented at idle and the amount of vacuum your engine makes. A low compression motor with less vacuum running higher boost may have a different adjustment than a stock compression motor with a small amount of boost.

At idle it should be open and there should be a large amount of air blowing out of it. However, it should snap shut quickly once you go full throttle.

 

so how many threads should there be with a stock compression motor with 2.87 pulley?