No kidding, on the vortech bypass. You def get a BOV sound??? Never heard one in person, or on the web... any links.. I would like to do it just to get the sound.... This is the same as the high $$ joint that procharger offers but half the price

 

This is how it looks on my kit.



You definetely get the "whoosh" sound. I get looks all the time whenever I gun it a little and then the bypass vents to boost. My wife always gives me a bad time about it. Says I'm trying out for "The Fast and the Furious lll"!
Eventually I'll plumb it back into the air filter intake tube on the passenger turbo to quite it down.

By the way, Rick at Synergy uses this on his 800+ WHP kits so it's plenty big enough for our applications.

Rick

 

And this is on your turbo or a blower set up?.. That nipple out of it gets a vac line hooked up correct, just like the standard Pcharger bypass.. BTW your old P1sc kit that I got from another guy is still working like a dream.. I just don't want it to waste the impeller on the blower..

 

This is on my turbo setup. It just hooks up like your procharger bypass valve.

I see used ones pop up for about $150 pretty regularly. I'll have to find you a link to a 3" cast aluminum adapter from eBay that works perfect with it and the Procharger head unit. You can see it in the photo I posted earlier. Use it and 2 90* silicone elbows to mount it right below the p-1sc.

Glad to hear one of my old kits is still working so good for you. I'm always impressed that you can run a full second faster on your rcsb. Makes me want a lighter truck.

Rick

 

Awsome a link would be great, since i see it needs a actual bolt on plate to work.. I just wonder how this works for a blower, but sounds like a BOV if infact it is a bypass.. I have never really looked into depth about them.. Just know a BOV isn't great for a centri blower

 

A blow off valve has a valve held closed by a spring. When you slam the throttle closed after building boost, the pressure spikes, overpowers the spring and pushes the valve opens momentarily to release the pressure, causing the whoosh sound.

A bypass valve has the same spring and valve system but also has a chamber to let manifold vacumn pull the valve open under light throttle (high vacumn) conditions.

You can search for "3" Aluminum adapter pipe" in the Turbo section on eBay. I also emailed you a link.

Rick

 

I have a TiAl BOV equipped with an eleven PSI spring. It has a vacuum/boost line from the intake manifold to the top of the BOV cover. This line supplies boost pressure when the intake manifold is under boost. This pressure adds to the spring pressure to hold the BOV closed when the intake manifold is under boost. The BOV valve does not open under boost conditions under any circumstances. The Waste Gate is designed to handle that function.

When you lift off the throttle quickly under high boost you close the throttle plate. This causes boost pressure to be trapped in the intake tubing to the TB because the FI device is still spinning fast. This in turn causes strain on the wheel and the TB plate. At the same time vacuum is created very quickly in the intake manifold because the engine is still at high rpm and pumping hard. Since the TB Plate is closed and little air can get into the engine a very high vacuum is created on deceleration. In my truck once the vacuum is > 11 psi the BOV is sucked open by the vacuum and the compressed air in the intake tubing is vented to the atmosphere. This helps to reduce or eliminate compressor surge and damage to the operating pieces in the intake.

That is the basics of how a BOV is set up to operate and it is quite different from the operation of a BY-pass valve which is set to open at cruise vacuum pressures to reduce the creation of boost pressure when cruising. This helps reduce fuel consumption by reducing the need for richer mixtures when cruising than would be required if boost and higher IATs were created when cruising.

 

What you descibed is exactly how a Blow off valve operates. I haven't heard of Blow Off Valves being open at idle but I've never had the opportunity to use one. When you look at the BOV and BPV's available on Vortech's website, they all look the same. I wouldn't be surprised if the only difference (other than most BPV have an exhaust port to allow air recirculation back into the intake track) was the spring rate. I believe the other big benefit to a bypass valve for MPG is the the reduced load on the engine under cruise. If the supercharger is spinning with little resistance, it's not eating up HP.

Rick

 

It is possible for BOVs to open at idle if you put too weak a spring in them. My vacuum at idle is ~ -9 psi and my BOV has an -11 psi (-11 psi = 22.4" of murcury not 11" of vacuum) spring so it should never open at idle. You can get a -9 psi spring for higher altitudes but here, near sea level, there is a chance it would open the valve at idle and allow unfiltered air into the intake. My engine will create enough vacuum at low speed deceleration to open the BOV a little but the TB plate is closed most of the way and the turbo is making a little pressure so that no air should get sucked into the intake. Or at least I hope not!

I agree that the SC spinning with little resistance at cruise would be a major benefit to fuel savings. Kind of forgot about that being a turbo guy...

 

I don't think you need to worry about unfiltered air getting sucked into the intake. On both my procharger and my turbo setups, the bypass valve is wide open at idle and you can feel air blowing out the valve. Even when I have someone blip the throttle hard, the air flow out the valve only increases till the vacumn drops enough for the valve to shut.

Rick