I believe he was referring to the bypass being open at idle and light throttle (not trying to haul ***). That is when it is open to vent air not needed by the motor... The SC puts out the same air at 4k rpm weather you are flooring it, or just slowly bring it up using light throttle. If you are not flooring it then the extra air from the blower (that the motor doesn't use) needs to go somewhere right?

 

You can try it. I have done it just for testing if the bypass valve works. The car seems fine too when the bypass was disconnected into the atmosphere. For this test, you should feel vacuum during idle (vacuum leak) then when you rev the car it will closed, and finally right when you closed the TB blades it will blow to release the boost you just made.

I actually think it won't work that well with the bypass venting to the atmosphere because the bypass is always open, so under street driving when you are seeing vacuum, you will have a vacuum leak (bypass always open). This is also why the BOV works because it is always closed.

If you have a boost guage, you can check to see if their is any vacuum drop with and without it being off. Even so, maybe a little vacuum leak maybe fine.

You probably shouldn't listen to me since I am running the BOV after the MAF for a couple of weeks now just for kicks and it's fine. I throw it on from time to time since I wasted the money for the BOV setup.

 

Huh??

 

It is possible to connect the surge valve to a switch. I have two surge valves. The first returns air to the blower inlet (as per design) on one of the twin IC branches. This one is connected AFTER the IC, which returns cooler air to the inlet. The second surge valve is located just before the second IC and it vents to atmosphere. This is hot non-ICd air. This valve is controlled either one of two ways:

With my switch in the off position, it stays closed all the time. In effect, it removes it from the system, allowing only my first valve to function. With the switch turned on, it vents to atmosphere, BUT IT ALSO CLOSES AUTOMATICALLY WHEN BOOST IS DETECTED. With this switch, I can have the "whooshing" sound whenever I want. But the most important aspect of being able to vent to atmosphere by turning on the switch is this: By doing this, the air temperature at the throttle body is significantly reduced, by around 20 degrees (year round).

Normally on a cold engine, the switch is off, preventing atmospheric venting. Once it has warmed up, I turned the switch on. It's amazing how I watch my digital air temp gauge showing air temps after the ICs drop as soon as I start venting to atmosphere.

Using this switch is only recommended in when multiple surge valves are used. With only one, you definitely don't want to close the valve under normal driving conditions -- it would be the same as not using a surge valve at all. So with a single valve system, you can vent to atmosphere but won't be able to revert back to "recirculating mode" with a switch.