So, I've had this Dejon Tool leak stop 1G DSM BOV on my Evo forever and I like it a lot for track stuff because of its part throttle characteristics, yet it worked great at 30 psi on my old FP Black set-up too. Here's my question: I did a boost leak check today and when I got north of 10-12 psi (not sure of exact pressure) the pneumatic valve started to vent through an unused open port on the rear of the Mac valve. When you connect the valve up, it uses two ports on the side and one on the front, but the rear port is unused and open. I'm not familiar enough with how this thing works to know whether that is normal or not, but it does worry me that I may have a massive boost leak. at least prior to the boost level at which the valve switches the BOV to its high boost leak-stop mode. If any old-timers can help me figure this out, I'd appreciate it. I think these things are out of production now and not too many Evo owners are running them. I guess my question is whether this is normal for this BOV. I don't recall it doing this in the past, but I may have just forgotten because it's been so long since I did a boost leak test. Thanks!

 

I should have waited before posting. It appears that it only leaks out that port when I pressurize the intake track to about 8 to 11 psi. Above that it seals up, so I think it's working the way it is supposed to -- like a leaky stock BOV at low boost and a highly sprung BOV at higher boost.